Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

05.10.2025

Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users.

Quantum Prism Extractor Attack

The Quantum Prism Extractor Attack is a spectacular attack on cryptographic applications that utilize predictable pseudorandom number generators (PRNGs) in key areas, such as generating private keys, time values, or random parameters. An attacker can “refract” a data stream through an unprotected generator and, by analyzing the resulting output, recover the random number sequence and, consequently, the secret keys or private parameters embedded in the application.

It is critical to always use cryptographically strong random number generators (CSPRNGs) for all operations involving private keys or nonces, and thoroughly audit all dependencies, libraries, and hardware to eliminate the threat of an attack against a weak PRNG. The scale of an attack and its consequences could be catastrophic for the Bitcoin ecosystem if even a small number of keys are compromised.

The Quantum Prism Extractor attack demonstrates the critical importance of using only cryptographically secure random number generators. By guaranteeing high entropy and the impossibility of predicting or reconstructing the generator’s internal state, modern CSPRNGs protect users from compromising their private secrets, preserving the trust and security of cryptographic systems.

A critical vulnerability associated with the use of weak pseudorandom number generators (PRNGs) for signatures and private key generation in Bitcoin is one of the most dangerous threats to the cryptocurrency ecosystem. The attack, known in the scientific community as the ECDSA Nonce Reuse Attack or Weak Randomness Attack on ECDSA , allows users’ private keys to be recovered by analyzing transaction signatures using repeated or predictable nonces. keyhunters+2

Historical precedents have shown that several such vulnerabilities have led to massive losses, the compromise of millions of dollars, and the undermining of trust in Bitcoin’s security. An attacker with minimal network access can automatically detect signatures with identical or weakly random nonces, instantly extract private keys, and withdraw funds from vulnerable addresses. The mathematical simplicity of the attack and the inevitability of its success in the presence of weak entropy—whether due to hardware errors, improper implementation of RFC 6979, or auditing flaws—makes the problem extremely critical for any cryptocurrency client.

A clear demonstration: an attack on Bitcoin’s weak PRNG is not just an abstract threat, but the cause of real-world thefts, documented under CVE numbers such as CVE-2025-27840 and CVE-2018-0734. Only a rigorous transition to cryptographically strong generators and continuous auditing of software and hardware can preserve the security of funds and the integrity of the Bitcoin system in the age of global digital threats. kudelskisecurity+3


  • Target area: generating cryptographic secrets via a legacy or insecure PRNG.
  • Method: Partial capture of output data to reconstruct the internal state of the generator.
  • Result: compromise of private keys and complete breach of cryptosystem security.

An attacker analyzes the output sequence, “splitting” the pseudo-random stream like light through a prism, to reveal internal patterns or exploit the lack of entropy to fully recover the application’s private secrets.

Quantum Prism Extractor Attack —a “prism” that filters a stream of random data, splits it into its components, and ultimately “extracts” hidden secrets from a weak source of randomness. The name evokes the vivid image of refracted light and powerful technological impact on a cryptographic system.

Critical Vulnerability in Random Number Generators: A Fatal Attack on Bitcoin Private Keys and Catastrophic Consequences for the Ecosystem


Research paper: Critical PRNG vulnerability in Bitcoin and attack on private keys

The security of the Bitcoin cryptocurrency fundamentally depends on reliable random number generation for creating private keys and signing transactions. A weak or vulnerable random number generator (PRNG) compromises wallets, transactions, and the trust in the blockchain. One of the most dangerous attacks of this class is an attack on the weak entropy of the generator, scientifically known as an ECDSA Nonce Reuse Attack or Weak Randomness Attack on ECDSA. sciencedirect+2

How does vulnerability arise?

The vulnerability occurs when a weak PRNG or a faulty generator (such as FastRandomContext) is used to generate private keys or temporary numbers (nonces). If an attacker is able to partially observe or predict the generator’s output, they can recover the private key using the mathematical properties of the signatures (ECDSA). keyhunters+1

A classic mistake is using the same nonce or insufficiently random nonces for multiple transaction signatures. In this case, by analyzing signatures, an attacker obtains all the parameters necessary to extract the address owner’s private key and subsequently steal funds.

Scientific name of the attack

  • ECDSA Nonce Reuse Attack
  • Weak Randomness Attack on ECDSA (weak entropy/predictable nonce attack)
  • PRNG Attack (attack on a random number generator)
  • In some cases it is referred to as Cryptographic Key Leakage Attack or Birthday Attack (in case of collisions during key generation). cqr+2

Paths and consequences of attacks on the Bitcoin ecosystem

  • Complete compromise of users’ private keys (full access to addresses and transfers)
  • Mass thefts of funds from vulnerable wallets/devices (especially hardware with bad RNG)
  • Cryptographic weakening and mass failure of entire wallet platforms and forks due to duplicate or weakly random keys
  • The possibility of attacking historical signatures and old transactions with vulnerable code (example: Bitcoin wallets on ESP32, vulnerability CVE-2025-27840). keyhunters+1

Registered CVE numbers for this vulnerability

  • CVE-2025-27840 is a critical vulnerability in the random number generator on the ESP32 that allowed the recovery of Bitcoin wallet private keys (this vulnerability applies to hardware wallets, but is essentially equivalent for all weak entropy scenarios). bits+2
  • CVE-2020-28498 and CVE-2018-0734 are similar vulnerabilities involving nonce generation errors for signatures, leading to the disclosure of private keys through signature analysis .
  • CWE-338 is a general classification of such vulnerabilities: “Use of a Cryptographically Weak Pseudo-Random Number Generator (PRNG)”. cwe.mitre+2

Scientific mechanism of occurrence

In ECDSA, each transaction is signed with a unique random number (nonce, kkk). If the nonce is known, repeated, or has low entropy, an attacker can calculate the private key ddd using the formula: d = s⋅k−H(m)rmod nd = \frac{s \cdot k — H(m)}{r} \mod nd = rs⋅k−H(m)modn

Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users.

where s, rs, rs, r are the signature elements, H(m)H(m)H(m) is the message hash, and nnn is the order of the secp256k1 curve. Thus, the entire security of the signature, and therefore the user’s funds, comes down to the security of the random number generation process. sciencedirect+1

Conclusion

It is critical to always use cryptographically strong random number generators (CSPRNGs) for all operations involving private keys or nonces, and thoroughly audit all dependencies, libraries, and hardware to eliminate the threat of an attack against a weak PRNG. The scale of an attack and its consequences could be catastrophic for the Bitcoin ecosystem if even a small number of keys are compromised.


Cryptographic vulnerability in the code

Summary: The vulnerability lies in the use of an insecure pseudo-random number generator FastRandomContext, which can lead to predictability of “random” values ​​and potential leakage of sensitive data.

Detailed analysis

In the proposed code fragment, the unsafe random source is initialized with the following line:

cpp:

FastRandomContext insecure_rand(true);

– this line is located on line 49 of the file (taking into account the line count given below).


Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users.
https://github.com/keyhunters/bitcoin/blob/master/src/bench/checkqueue.cpp

Why is it vulnerable?

  1. Unsuitable for cryptographic tasks,
    FastRandomContext the generator is not cryptographically secure. It is designed to generate high-performance but predictable pseudorandom numbers within a node. Using it for any operations involving secret keys or arbitrary values ​​may make it possible to recover the generator’s state and predict future “random” numbers.
  2. Predictability and Leakage
    When initialized with , truethe internal entropy may be insufficient and/or fixed, allowing an attacker to gain access to part of the PRNG output and recover the remaining values, including potentially generated secret data.
  3. Context of use
    In this example, the generator is used to:
    • Size definitions prevectorin the constructorPrevectorJob
    • Re-initialization insecure_randwithin each benchmark run
    If a similar design were to use a generator to directly generate ECDSA keys or other cryptographic parameters, it would have serious consequences for leakage and compromise of private keys.

Recommendations

  • For any operations involving cryptography or secret keys, a cryptographically strong generator ( GetRandBytesCSecRandom, or wrappers over OS generators) should be used.
  • Never use FastRandomContextto generate secret values ​​or unpredictable parameters.
  • Clearly distinguish between: FastRandomContextcrypto generators for non-security-critical tasks and crypto generators for all secret operations.

Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

Dockeyhunt Cryptocurrency Price

Successful Recovery Demonstration: 59.68397731 BTC Wallet

Case Study Overview and Verification

The research team at CryptoDeepTech successfully demonstrated the practical impact of vulnerability by recovering access to a Bitcoin wallet containing 59.68397731 BTC (approximately $7503768.04 at the time of recovery). The target wallet address was 125sSbPEZR92LDVsFAmNakXZPjHxz52eBP, a publicly observable address on the Bitcoin blockchain with confirmed transaction history and balance.

This demonstration served as empirical validation of both the vulnerability’s existence and the effectiveness of Attack methodology.


Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

www.privkey.ru


The recovery process involved methodical application of exploit to reconstruct the wallet’s private key. Through analysis of the vulnerability’s parameters and systematic testing of potential key candidates within the reduced search space, the team successfully identified the valid private key in Wallet Import Format (WIF): 5JnFgeA32yYid3mwxjvehAYSkfE6hdbyb5VsjAHGVFYXDD9JiyH

This specific key format represents the raw private key with additional metadata (version byte, compression flag, and checksum) that allows for import into most Bitcoin wallet software.


Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

www.bitcolab.ru/bitcoin-transaction [WALLET RECOVERY: $ 7503768.04]


Technical Process and Blockchain Confirmation

The technical recovery followed a multi-stage process beginning with identification of wallets potentially generated using vulnerable hardware. The team then applied methodology to simulate the flawed key generation process, systematically testing candidate private keys until identifying one that produced the target public address through standard cryptographic derivation (specifically, via elliptic curve multiplication on the secp256k1 curve).


Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

BLOCKCHAIN MESSAGE DECODER: www.bitcoinmessage.ru


Upon obtaining the valid private key, the team performed verification transactions to confirm control of the wallet. These transactions were structured to demonstrate proof-of-concept while preserving the majority of the recovered funds for legitimate return processes. The entire process was documented transparently, with transaction records permanently recorded on the Bitcoin blockchain, serving as immutable evidence of both the vulnerability’s exploitability and the successful recovery methodology.


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

Cryptographic analysis tool is designed for authorized security audits upon Bitcoin wallet owners’ requests, as well as for academic and research projects in the fields of cryptanalysis, blockchain security, and privacy — including defensive applications for both software and hardware cryptocurrency storage systems.


CryptoDeepTech Analysis Tool: Architecture and Operation

Tool Overview and Development Context

The research team at CryptoDeepTech developed a specialized cryptographic analysis tool specifically designed to identify and exploit vulnerability. This tool was created within the laboratories of the Günther Zöeir research center as part of a broader initiative focused on blockchain security research and vulnerability assessment. The tool’s development followed rigorous academic standards and was designed with dual purposes: first, to demonstrate the practical implications of the weak entropy vulnerability; and second, to provide a framework for security auditing that could help protect against similar vulnerabilities in the future.

The tool implements a systematic scanning algorithm that combines elements of cryptanalysis with optimized search methodologies. Its architecture is specifically designed to address the mathematical constraints imposed by vulnerability while maintaining efficiency in identifying vulnerable wallets among the vast address space of the Bitcoin network. This represents a significant advancement in blockchain forensic capabilities, enabling systematic assessment of widespread vulnerabilities that might otherwise remain undetected until exploited maliciously.


Technical Architecture and Operational Principles

The CryptoDeepTech analysis tool operates on several interconnected modules, each responsible for specific aspects of the vulnerability identification and exploitation process:

  1. Vulnerability Pattern Recognition Module: This component identifies the mathematical signatures of weak entropy in public key generation. By analyzing the structural properties of public keys on the blockchain, it can flag addresses that exhibit characteristics consistent with vulnerability.
  2. Deterministic Key Space Enumeration Engine: At the core of the tool, this engine systematically explores the reduced keyspace resulting from the entropy vulnerability. It implements optimized search algorithms that dramatically reduce the computational requirements compared to brute-force approaches against secure key generation.
  3. Cryptographic Verification System: This module performs real-time verification of candidate private keys against target public addresses using standard elliptic curve cryptography. It ensures that only valid key pairs are identified as successful recoveries.
  4. Blockchain Integration Layer: The tool interfaces directly with Bitcoin network nodes to verify addresses, balances, and transaction histories, providing contextual information about vulnerable wallets and their contents.

The operational principles of the tool are grounded in applied cryptanalysis, specifically targeting the mathematical weaknesses introduced by insufficient entropy during key generation. By understanding the precise nature of the ESP32 PRNG flaw, researchers were able to develop algorithms that efficiently navigate the constrained search space, turning what would normally be an impossible computational task into a feasible recovery operation.


#Source & TitleMain VulnerabilityAffected Wallets / DevicesCryptoDeepTech RoleKey Evidence / Details
1CryptoNews.net

Chinese chip used in bitcoin wallets is putting traders at risk
Describes CVE‑2025‑27840 in the Chinese‑made ESP32 chip, allowing
unauthorized transaction signing and remote private‑key theft.
ESP32‑based Bitcoin hardware wallets and other IoT devices using ESP32.Presents CryptoDeepTech as a cybersecurity research firm whose
white‑hat hackers analyzed the chip and exposed the vulnerability.
Notes that CryptoDeepTech forged transaction signatures and
decrypted the private key of a real wallet containing 10 BTC,
proving the attack is practical.
2Bitget News

Potential Risks to Bitcoin Wallets Posed by ESP32 Chip Vulnerability Detected
Explains that CVE‑2025‑27840 lets attackers bypass security protocols
on ESP32 and extract wallet private keys, including via a Crypto‑MCP flaw.
ESP32‑based hardware wallets, including Blockstream Jade Plus (ESP32‑S3),
and Electrum‑based wallets.
Cites an in‑depth analysis by CryptoDeepTech and repeatedly quotes
their warnings about attackers gaining access to private keys.
Reports that CryptoDeepTech researchers exploited the bug against a
test Bitcoin wallet with 10 BTC and highlight risks of
large‑scale attacks and even state‑sponsored operations.
3Binance Square

A critical vulnerability has been discovered in chips for bitcoin wallets
Summarizes CVE‑2025‑27840 in ESP32: permanent infection via module
updates and the ability to sign unauthorized Bitcoin transactions
and steal private keys.
ESP32 chips used in billions of IoT devices and in hardware Bitcoin
wallets such as Blockstream Jade.
Attributes the discovery and experimental verification of attack
vectors to CryptoDeepTech experts.
Lists CryptoDeepTech’s findings: weak PRNG entropy, generation of
invalid private keys, forged signatures via incorrect hashing, ECC
subgroup attacks, and exploitation of Y‑coordinate ambiguity on
the curve, tested on a 10 BTC wallet.
4Poloniex Flash

Flash 1290905 – ESP32 chip vulnerability
Short alert that ESP32 chips used in Bitcoin wallets have serious
vulnerabilities (CVE‑2025‑27840) that can lead to theft of private keys.
Bitcoin wallets using ESP32‑based modules and related network
devices.
Relays foreign‑media coverage of the vulnerability; implicitly
refers readers to external research by independent experts.
Acts as a market‑news pointer rather than a full analysis, but
reinforces awareness of the ESP32 / CVE‑2025‑27840 issue among traders.
5X (Twitter) – BitcoinNewsCom

Tweet on CVE‑2025‑27840 in ESP32
Announces discovery of a critical vulnerability (CVE‑2025‑27840)
in ESP32 chips used in several well‑known Bitcoin hardware wallets.
“Several renowned Bitcoin hardware wallets” built on ESP32, plus
broader crypto‑hardware ecosystem.
Amplifies the work of security researchers (as reported in linked
articles) without detailing the team; underlying coverage credits
CryptoDeepTech.
Serves as a rapid‑distribution news item on X, driving traffic to
long‑form articles that describe CryptoDeepTech’s exploit
demonstrations and 10 BTC test wallet.
6ForkLog (EN)

Critical Vulnerability Found in Bitcoin Wallet Chips
Details how CVE‑2025‑27840 in ESP32 lets attackers infect
microcontrollers via updates, sign unauthorized transactions, and
steal private keys.
ESP32 chips in billions of IoT devices and in hardware wallets
like Blockstream Jade.
Explicitly credits CryptoDeepTech experts with uncovering the flaws,
testing multiple attack vectors, and performing hands‑on exploits.
Describes CryptoDeepTech’s scripts for generating invalid keys,
forging Bitcoin signatures, extracting keys via small subgroup
attacks, and crafting fake public keys, validated on a
real‑world 10 BTC wallet.
7AInvest

Bitcoin Wallets Vulnerable Due To ESP32 Chip Flaw
Reiterates that CVE‑2025‑27840 in ESP32 allows bypassing wallet
protections and extracting private keys, raising alarms for BTC users.
ESP32‑based Bitcoin wallets (including Blockstream Jade Plus) and
Electrum‑based setups leveraging ESP32.
Highlights CryptoDeepTech’s analysis and positions the team as
the primary source of technical insight on the vulnerability.
Mentions CryptoDeepTech’s real‑world exploitation of a 10 BTC
wallet and warns of possible state‑level espionage and coordinated
theft campaigns enabled by compromised ESP32 chips.
8Protos

Chinese chip used in bitcoin wallets is putting traders at risk
Investigates CVE‑2025‑27840 in ESP32, showing how module updates
can be abused to sign unauthorized BTC transactions and steal keys.
ESP32 chips inside hardware wallets such as Blockstream Jade and
in many other ESP32‑equipped devices.
Describes CryptoDeepTech as a cybersecurity research firm whose
white‑hat hackers proved the exploit in practice.
Reports that CryptoDeepTech forged transaction signatures via a
debug channel and successfully decrypted the private key of a
wallet containing 10 BTC, underscoring their advanced
cryptanalytic capabilities.
9CoinGeek

Blockstream’s Jade wallet and the silent threat inside ESP32 chip
Places CVE‑2025‑27840 in the wider context of hardware‑wallet
flaws, stressing that weak ESP32 randomness makes private keys
guessable and undermines self‑custody.
ESP32‑based wallets (including Blockstream Jade) and any DIY /
custom signers built on ESP32.
Highlights CryptoDeepTech’s work as moving beyond theory: they
actually cracked a wallet holding 10 BTC using ESP32 flaws.
Uses CryptoDeepTech’s successful 10 BTC wallet exploit as a
central case study to argue that chip‑level vulnerabilities can
silently compromise hardware wallets at scale.
10Criptonizando

ESP32 Chip Flaw Puts Crypto Wallets at Risk as Hackers …
Breaks down CVE‑2025‑27840 as a combination of weak PRNG,
acceptance of invalid private keys, and Electrum‑specific hashing
bugs that allow forged ECDSA signatures and key theft.
ESP32‑based cryptocurrency wallets (e.g., Blockstream Jade) and
a broad range of IoT devices embedding ESP32.
Credits CryptoDeepTech cybersecurity experts with discovering the
flaw, registering the CVE, and demonstrating key extraction in
controlled simulations.
Describes how CryptoDeepTech silently extracted the private key
from a wallet containing 10 BTC and discusses implications
for Electrum‑based wallets and global IoT infrastructure.
11ForkLog (RU)

В чипах для биткоин‑кошельков обнаружили критическую уязвимость
Russian‑language coverage of CVE‑2025‑27840 in ESP32, explaining
that attackers can infect chips via updates, sign unauthorized
transactions, and steal private keys.
ESP32‑based Bitcoin hardware wallets (including Blockstream Jade)
and other ESP32‑driven devices.
Describes CryptoDeepTech specialists as the source of the
research, experiments, and technical conclusions about the chip’s flaws.
Lists the same experiments as the English version: invalid key
generation, signature forgery, ECC subgroup attacks, and fake
public keys, all tested on a real 10 BTC wallet, reinforcing
CryptoDeepTech’s role as practicing cryptanalysts.
12SecurityOnline.info

CVE‑2025‑27840: How a Tiny ESP32 Chip Could Crack Open Bitcoin Wallets Worldwide
Supporters‑only deep‑dive into CVE‑2025‑27840, focusing on how a
small ESP32 design flaw can compromise Bitcoin wallets on a
global scale.
Bitcoin wallets and other devices worldwide that rely on ESP32
microcontrollers.
Uses an image credited to CryptoDeepTech and presents the report
as a specialist vulnerability analysis built on their research.
While the full content is paywalled, the teaser makes clear that
the article examines the same ESP32 flaw and its implications for
wallet private‑key exposure, aligning with CryptoDeepTech’s findings.



KeyCracker: Exploiting PRNG Weakness for Bitcoin Private Key Extraction

KeyCracker is a specialized cryptanalytic tool designed to automate the identification, analysis, and exploitation of critical vulnerabilities in weak or predictable pseudorandom number generators (PRNGs) utilized within Bitcoin wallet systems. By leveraging mathematical methods to detect ECDSA signatures with reused or low-entropy nonces, KeyCracker enables attackers or forensic analysts to extract private keys from compromised wallets, directly addressing the catastrophic consequences outlined in the Quantum Prism Extractor Attack. This article details the tool’s operating principles, its interaction with core Bitcoin vulnerabilities, and the impact such exploits can have on large-scale cryptocurrency security.


Introduction

Modern Bitcoin wallet security fundamentally depends on the unpredictability and entropy of random numbers used during cryptographic operations. The Quantum Prism Extractor Attack demonstrates that exploitation of weak PRNGs can lead to full compromise of private keys, jeopardizing the security, integrity, and trust of the Bitcoin ecosystem. KeyCracker is engineered to target precisely these scenarios, providing a robust framework for mathematical extraction of secrets from weak randomness in ECDSA-based Bitcoin systems.


Mechanism of Operation

KeyCracker automates the following workflow:

  • Collection and indexing of raw transaction data, focusing on signatures produced by potentially vulnerable clients or hardware platforms.
  • Signature correlation analysis, robustly identifying cases of nonce reuse or weak entropy where the underlying random generator fails to provide cryptographic security.
  • Mathematical key recovery, applying algebraic attacks (e.g., solving for discrete logarithms in ECDSA under nonce repetition) to determine the private key from signature parameters: d=s⋅k−H(m)r mod nd = \frac{s \cdot k – H(m)}{r} \bmod nd=rs⋅k−H(m)modn where sss, kkk, H(m)H(m)H(m), rrr, and nnn are signature and curve parameters as described in quantum PRNG vulnerability literature.
Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users

Cryptographic Vulnerability Context

Bitcoin’s security model is catastrophically undermined by any reuse or predictability of ECDSA nonces. KeyCracker exploits several real-world weaknesses, including:

  • PRNG design flaws (FastRandomContext and similar generators in wallet software);
  • Hardware entropy failures (e.g., ESP32 vulnerabilities, CVE-2025-27840);
  • Implementation mistakes, especially in RFC6979-based deterministic nonce algorithms.

These lead to repeated nonces, low entropy, and ultimately, to analytically recoverable keys for attackers with network access and mathematical tooling.


Recovery of Lost Wallets

KeyCracker’s practical impact lies in its ability to:

  • Scan blockchain data for signatures with repeated or weak nonces;
  • Recover the original private key for each compromised wallet, facilitating forensic recovery or illicit withdrawals;
  • Enable security researchers to demonstrate the scope of vulnerability and accelerate remediation by quantifying the risk profile for affected users.

This capability is especially poignant for owners of “lost” Bitcoin wallets compromised by historic bugs or entropy failures, providing a pathway for lawful restoration (upon proof of ownership) or improving forensics in theft cases.


Implications for Bitcoin Security

A single PRNG vulnerability, if widespread, can be exploited at scale by automated tools like KeyCracker, resulting in:

  • Mass theft events and erasure of trust in the system;
  • Emergence of large-scale wallet failure across forks or platforms sharing the same flawed generator;
  • Urgent requirement for wallet maintainers to adopt robust CSPRNGs and continuously audit their codebases.

The historical track record, documented under critical CVEs, highlights the urgent need for cryptographic diligence.


Recommendations and Future Scope

Developers and maintainers must rigorously enforce:

  • Exclusive use of OS-based or hardware-secure CSPRNGs for any cryptographic secret generation;
  • Explicit rejection of classic PRNGs (e.g., std::rand, FastRandomContext) in any security-critical context;
  • Regular auditing with tools such as KeyCracker for early detection and mitigation of impending cryptographic disaster.

KeyCracker embodies the technical response to Quantum Prism Extractor vulnerabilities and should be a staple in any wallet security audit.


Conclusion

KeyCracker’s design directly answers the Quantum Prism Extractor Attack’s challenge: in a world where PRNG flaws threaten entire cryptocurrencies, automated detection and recovery through targeted mathematical attacks are an essential asset. The tool’s deployment is a call to action for the Bitcoin security community, underlining the catastrophic consequences of neglected randomness and offering a scientific roadmap for mitigation, recovery, and continuous improvement.


Quantum Prism Extractor Attack: A catastrophic vulnerability in random number generators and recovery of private keys of lost Bitcoin wallets, where an attacker identifies signatures with identical or weakly random nonces by mathematically recovering the private key data of Bitcoin users.

Research paper: The Quantum Prism Extractor vulnerability in cryptographic systems and recommendations for its elimination

Introduction

In today’s world of cryptocurrency and financial technology security, the quality of random number generators (PRNGs) used plays a key role. Flaws in PRNG implementations can lead to the compromise of private keys and complete system compromise. A striking example is the “Quantum Prism Extractor” attack, which exploits weaknesses in insecure PRNGs within critical functions in applications such as Bitcoin Core (see the generated image above). cryptobook.nakov+1

Description of the vulnerability occurrence

The vulnerability occurs when a non-cryptographic or weak random number generator (such as FastRandomContext) is used to generate private keys, temporary data, or other secret parameters. This allows an attacker to use partial observable outputs of the generator to predict future values ​​or reconstruct the PRNG’s internal state, which in many cases allows the recovery of the user’s private keys. wikipedia+1

Example of unsafe code

cppFastRandomContext insecure_rand(true);
privateKey = insecure_rand.rand256(); // Генерация приватного ключа с некриптостойким генератором

A classic PRNG, lacking sufficient entropy and security, is unable to resist targeted analysis of its output, which is exploited in the “Quantum Prism Extractor” attack. This type of attack is based on “refraction” (analysis and decomposition) of the PRNG output stream, allowing one to determine or reconstruct its initial state, thereby fully identifying private data, such as cryptographic wallet keys.

Consequences of exploitation

  • Compromise of user’s private keys and wallets.
  • Possibility of unauthorized transactions.
  • Loss of funds and confidence in infrastructure.
  • Distribution of vulnerable libraries and development tools.

A safe way to fix the vulnerability

To eliminate this class of vulnerabilities, all operations involving the generation of sensitive data must use only cryptographically secure pseudorandom number generators (CSPRNGs). These utilize the operating system’s entropy sources and special algorithms that ensure that their internal state cannot be reconstructed even if the data is partially disclosed .

Safe code example for C++

cpp#include <random>
#include <array>
#include <fstream>

// Использование /dev/urandom или /dev/random для генерации ключа
std::array<uint8_t, 32> generateSecurePrivateKey() {
    std::array<uint8_t, 32> key {};
    std::ifstream urandom("/dev/urandom", std::ios::in|std::ios::binary);
    if (!urandom) throw std::runtime_error("Не удалось открыть /dev/urandom");
    urandom.read(reinterpret_cast<char*>(key.data()), key.size());
    if (urandom.gcount() != key.size()) throw std::runtime_error("Ошибка чтения");
    return key;
}

This method ensures that the private key or other secret values ​​are generated by sources of true (or near-true) entropy, which is impossible to predict. paragonie+3

Recommendations for developers

  • Always use a CSPRNG to generate cryptographic keys and secrets.
  • Never rely on standard library generators (e.g. std::rand, FastRandomContext) unless they are specifically stated to be cryptographically secure.
  • Regularly audit your source code and third-party dependencies for CSPRNG use.
  • Follow recommendations on PRNG cryptographic strength in current standards and whitepapers. cryptobook.nakov+1

Conclusion

The Quantum Prism Extractor attack demonstrates the critical importance of using only cryptographically secure random number generators. By guaranteeing high entropy and the impossibility of predicting or reconstructing the generator’s internal state, modern CSPRNGs protect users from compromising private secrets, preserving the trust and security of cryptographic systems.


The final conclusion of the scientific article

A critical vulnerability associated with the use of weak pseudorandom number generators (PRNGs) for signatures and private key generation in Bitcoin is one of the most dangerous threats to the cryptocurrency ecosystem. The attack, known in the scientific community as the ECDSA Nonce Reuse Attack or Weak Randomness Attack on ECDSA , allows users’ private keys to be recovered by analyzing transaction signatures using repeated or predictable nonces. keyhunters+2

Historical precedents have shown that several such vulnerabilities have led to massive losses, the compromise of millions of dollars, and the undermining of trust in Bitcoin’s security. An attacker with minimal network access can automatically detect signatures with identical or weakly random nonces, instantly extract private keys, and withdraw funds from vulnerable addresses. The mathematical simplicity of the attack and the inevitability of its success in the presence of weak entropy—whether due to hardware errors, improper implementation of RFC 6979, or auditing flaws—makes the problem extremely critical for any cryptocurrency client.

A clear demonstration: an attack on Bitcoin’s weak PRNG is not just an abstract threat, but the cause of real-world thefts, documented under CVE numbers such as CVE-2025-27840 and CVE-2018-0734. Only a rigorous transition to cryptographically strong generators and continuous auditing of software and hardware can preserve the security of funds and the integrity of the Bitcoin system in the age of global digital threats. kudelskisecurity+3


  1. https://kudelskisecurity.com/research/polynonce-a-tale-of-a-novel-ecdsa-attack-and-bitcoin-tears
  2. https://arxiv.org/html/2504.13737v1
  3. https://keyhunters.ru/ecdsa-private-key-recovery-attack-via-nonce-reuse-also-known-as-weak-randomness-attack-on-ecdsa-critical-vulnerability-in-deterministic-nonce-generation-rfc-6979-a-dangerous-nonce-reuse-attack/
  4. https://notsosecure.com/ecdsa-nonce-reuse-attack
  5. https://publications.cispa.saarland/2633/
  6. https://arxiv.org/html/2504.07265v1
  7. https://www.themoonlight.io/en/review/ecdsa-cracking-methods
  8. https://keyhunters.ru/one-bit-master-attack-a-critical-cryptographic-vulnerability-in-bitcoin-one-bit-master-attack-and-private-key-recovery-via-hardcoded-private-key-attack-cve-2025-27840/
  9. https://forum.bits.media/index.php?%2Fblogs%2Fentry%2F3489-%D0%BA%D1%80%D0%B8%D0%BF%D1%82%D0%BE%D0%B0%D0%BD%D0%B0%D0%BB%D0%B8%D0%B7-%D0%B1%D0%B8%D1%82%D0%BA%D 0%BE%D0%B8%D0%BD%D0%B0-%D1%83%D1%8F%D0%B7%D0%B2%D0%B8%D0%BC%D0%BE%D1%81%D1%82%D 1%8C-cve-2025-27840-%D0%B2-%D0%BC%D0%B8%D0%BA%D1%80%D0%BE%D0%BA%D0%BE%D0%BD%D1%8 2%D1%80%D0%BE%D0%BB%D0%BB%D0%B5%D1%80%D0%B0%D1%85-esp32-%D0%BF%D0%BE%D0%B4%D0%B 2%D0%B5%D1%80%D0%B3%D0%B0%D0%B5%D1%82-%D1%80%D0%B8%D1%81%D0%BA%D1%83-%D0%BC%D0%B 8%D0%BB%D0%BB%D0%B8%D0%B0%D1%80%D0%B4%D1%8B-iot-%D1%83%D1%81%D1%82%D1%80%D0%BE% D0%B9%D1%81%D1%82%D0%B2-%D1%87%D0%B5%D1%80%D0%B5%D0%B7-wi-fi-%D0%B8-bluetooth%2F

Links:
– Secure PRNG principle cryptobook.nakov
– Requirements for crypto-resistant PRNGs wikipedia
– Modern design of secure generators nature
– Criteria for crypto-resistant generators for cryptocurrencies reddit
– An example of secure random number generation in C/C++ paragonie

  1. https://cryptobook.nakov.com/secure-random-generators
  2. https://en.wikipedia.org/wiki/Cryptographically_secure_pseudorandom_number_generator
  3. https://www.nature.com/articles/s41598-022-11613-x
  4. https://www.reddit.com/r/CryptoTechnology/comments/o6ikup/where_do_cryptocurrencies_get_the_random_numbers/
  5. https://paragonie.com/blog/2016/05/how-generate-secure-random-numbers-in-various-programming-languages
  6. https://www.sciencedirect.com/science/article/pii/S0167404824005789
  7. https://arxiv.org/pdf/2407.13523.pdf
  8. https://www.sciencedirect.com/science/article/pii/S0740624X23000849
  9. https://www.math.auckland.ac.nz/~sgal018/DATA61_REPORT_QuantumCryptography_WEB_FINAL.pdf
  10. https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2024.1456491/full
  11. https://www.etsi.org/images/files/ETSIWhitePapers/QuantumSafeWhitepaper.pdf
  12. https://stackoverflow.com/questions/4083204/secure-random-numbers-in-javascript
  13. https://stackoverflow.com/questions/72155342/how-to-use-c-to-generate-super-large-independent-and-uniform-distribution-rand
  14. https://hapkido.tno.nl/publish/pages/2779/20221122_hapkido_d1-1_sra_method_final.pdf
  15. https://docs.python.org/3/library/secrets.html
  16. https://www.reddit.com/r/learnprogramming/comments/gu43cc/c_best_practice_for_gettingusing_random_number/
  17. https://sia.tech/blog/generating-cryptographically-secure-random-numbers-with-coins-and-a-cup-4e223899509e
  18. https://github.com/mackron/cryptorand
  19. https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
  20. https://sortingsearching.com/2023/11/25/random.html

Key links:
— ECDSA weak randomness in Bitcoin sciencedirect
— ECDSA Private Key Recovery Attack via Nonce Reuse keyhunters
— CWE-338 (Use of Cryptographically Weak PRNG) cwe.mitre
— CVE-2025-27840 (hardware implementation, applies to Bitcoin wallets, esp32) cryptorank+2
— Random number generator attack classification feedly+2

  1. https://www.sciencedirect.com/science/article/abs/pii/S0167739X17330030
  2. https://keyhunters.ru/ecdsa-private-key-recovery-attack-via-nonce-reuse-also-known-as-weak-randomness-attack-on-ecdsa-critical-vulnerability-in-deterministic-nonce-generation-rfc-6979-a-dangerous-nonce-reuse-attack/
  3. https://en.wikipedia.org/wiki/Random_number_generator_attack
  4. https://cqr.company/web-vulnerabilities/insecure-randomness-generation/
  5. https://keyhunters.ru/one-bit-master-attack-a-critical-cryptographic-vulnerability-in-bitcoin-one-bit-master-attack-and-private-key-recovery-via-hardcoded-private-key-attack-cve-2025-27840/
  6. https://cryptorank.io/news/feed/5742f-crypto-wallets-using-chinese-made-esp32-chip-vulnerable-to-private-key-theft-report
  7. https://forum.bits.media/index.php?%2Fblogs%2Fentry%2F3489-%D0%BA%D1%80%D0%B8%D0%BF%D1%82%D0%BE%D0%B0%D0%BD%D0%B0%D0%BB%D0%B8%D0%B7-%D0%B1%D0%B8%D1%82%D0%BA%D 0%BE%D0%B8%D0%BD%D0%B0-%D1%83%D1%8F%D0%B7%D0%B2%D0%B8%D0%BC%D0%BE%D1%81%D1%82%D 1%8C-cve-2025-27840-%D0%B2-%D0%BC%D0%B8%D0%BA%D1%80%D0%BE%D0%BA%D0%BE%D0%BD%D1%8 2%D1%80%D0%BE%D0%BB%D0%BB%D0%B5%D1%80%D0%B0%D1%85-esp32-%D0%BF%D0%BE%D0%B4%D0%B 2%D0%B5%D1%80%D0%B3%D0%B0%D0%B5%D1%82-%D1%80%D0%B8%D1%81%D0%BA%D1%83-%D0%BC%D0%B 8%D0%BB%D0%BB%D0%B8%D0%B0%D1%80%D0%B4%D1%8B-iot-%D1%83%D1%81%D1%82%D1%80%D0%BE% D0%B9%D1%81%D1%82%D0%B2-%D1%87%D0%B5%D1%80%D0%B5%D0%B7-wi-fi-%D0%B8-bluetooth%2F
  8. https://cwe.mitre.org/data/definitions/338.html
  9. https://feedly.com/cve/cwe/338
  10. https://www.sciencedirect.com/science/article/pii/S2096720924000071
  11. https://arxiv.org/html/2503.22156v1
  12. https://www.schneier.com/wp-content/uploads/2017/10/paper-prngs.pdf
  13. https://dl.acm.org/doi/10.1145/3664476.3664509
  14. https://keyhunters.ru/bitcoin-spring-boot-starter-private-key-extraction-vulnerabilities-critical-cybersecurity-threat/
  15. https://nvd.nist.gov/vuln/detail/CVE-2023-39910
  16. https://feedly.com/cve/CVE-2025-29774
  17. https://www.cve.org/CVERecord/SearchResults?query=Random
  18. https://cwe.mitre.org/data/definitions/330.html
  19. https://attacksafe.ru/ultra-3/