Main Hacking Attack Methods and New Smart Contract Vulnerabilities in the Crypto Industry in 2025: Social Engineering, Phishing, and Off-Chain Attacks as the Main Security Threats

In July 2025, the crypto industry suffered significant losses of at least $142 million from 17 separate hacks, up 27% from the previous month, when losses totaled $111 million. However, this figure remains 46% lower than the July 2024 level, when hackers stole a record $266 million, the lion’s share of which – $230 million – came from the hack of the Indian exchange WazirX 1 7 .

The biggest incident of the month happened with the Indian crypto exchange CoinDCX, which lost $44 million in a complex attack on its servers on July 18. According to CoinDCX CEO Sumit Gupta, the attackers gained access to the company’s storage through malware installed on the laptop of an employee, Rahul Agarwal. Agarwal was misled by the scammers, who offered him a part-time job remotely, for which he received about $18 thousand. Subsequently, he did not necessarily become a tool for the criminals, but it was through his device that the attack was carried out, allowing the funds to be transferred to third-party wallets. In connection with the incident, the employee was arrested 3 [web:
The second largest hack occurred on July 11 on the decentralized exchange GMX, where hackers stole $40 million. Notably, a few days later the attacker returned the stolen funds, as reported by the analytics company PeckShield 1 7 .

Two days before the CoinDCX hack, on July 16, the BigONE exchange suffered: hackers attacked the hot wallet infrastructure, stealing about $27 million. The third largest damage was caused to the WOO X trading platform, which fell victim to a $14 million phishing attack on July 24 1 7 .

According to Rob Behnke, chairman of blockchain security firm Halborn, the WOO X hack was carried out through social engineering: the attackers managed to gain access to an employee’s computer by using the system’s trust mechanisms to withdraw funds from user accounts. The attack lasted for about two hours until the suspicious activity was detected, after which the platform disabled withdrawals. The funds were stored on various blockchains, including Bitcoin (BTC), Ethereum (ETH), Binance Coin (BNB), and Arbitrum (ARB). All affected accounts were restored using the company’s reserves 1 .

Experts note that hackers are changing their tactics: instead of searching for vulnerabilities in smart contracts that can be eliminated through auditing, they are increasingly attacking off-chain systems – servers, internal infrastructure and processes of companies. This is due to the fact that vulnerabilities in such systems are more profitable and more difficult to detect. As a result, projects need to implement more reliable security control mechanisms and develop clear procedures to minimize threats from intruders 1 .

Thus, July 2025 became another period of serious security tests for crypto exchanges. Hacks of such major platforms as CoinDCX, GMX, BigONE and WOO X resulted in multi-million dollar losses and revealed new methods used by cybercriminals. Effectively countering these threats requires a comprehensive approach to security, including both smart contract audits and strengthening the protection of internal systems and the human factor.

Main Hacker Attack Methods and New Smart Contract Vulnerabilities in the Crypto Industry in 2025: Social Engineering, Phishing, and Off-Chain Attacks as the Main Security Threats

What are the main methods hackers use to hack crypto exchanges in 2025

In 2025, hackers use several main methods when hacking crypto exchanges, among which the following stand out:

Social engineering. This is the key and most common attack vector aimed at the human factor – deception and manipulation of exchange employees. Attackers can bribe employees, impersonate trusted persons, use fake job offers and other methods to gain access to internal systems. In one of the known cases, an employee of the Indian exchange CoinDCX became an indirect victim of fraudulent actions, which led to the loss of $ 44 million 11 12 2 .
Phishing attacks. Hackers create fake websites, emails, or messages disguised as official services and interfaces of crypto exchanges, wallets, or exchangers. Victims enter their data and receive stolen passwords, seed phrases, or keys. Modern phishing attacks are often enhanced with artificial intelligence and deepfakes, making them highly effective and difficult to detect[web1].
Attacks on hot and cold wallet infrastructure. For example, hackers penetrate hot wallet infrastructure, as happened with the BigONE exchange, where $27 million was stolen. Also, major hacks exploit vulnerabilities in multi-signature wallets and their interfaces, forging transaction data (for example, the Bybit hack for $1.4 billion) 4 12 10 .
Using social engineering methods with elements of deepfake and interface substitution. Hackers can slip malicious files to employees through supposedly official emails, create fake interfaces for multi-signature systems, which forces employees to make fraudulent transactions without noticing the substitution of data 3 4 6 .
Attacks on internal off-chain systems. As smart contracts become more secure, hackers are turning to vulnerabilities in companies’ internal infrastructure — servers, internal processes, and employee devices. These attacks are harder to detect and can generate significant revenue 12 .
Theft of users’ private keys and seed phrases through hacking of user devices and phishing remains a significant cause of loss of funds 2 .

Taken together, modern hacking methods in the crypto industry in 2025 are a combination of technological threats and human errors, requiring a comprehensive approach to security – from technical audits and monitoring to employee training and increased access control. In 2025, hackers use several main methods when hacking crypto exchanges:

Social engineering is a major attack vector, involving deceiving, bribing, or misleading employees to gain access to internal systems. An example is the CoinDCX employee whose device was the subject of a major hack 11 12 2 .
Phishing attacks are fake websites and emails that disguise themselves as official exchanges and wallets, with the goal of stealing passwords and private keys. These attacks are often amplified by AI and deepfakes 3 1 .
Attacks on hot and cold wallet infrastructure, including interface substitution (e.g. multi-signature), which allows for the theft of large sums, as in the $1.4 billion Bybit hack 4 10 12 .
Using deepfake and spoofing interfaces to conduct fraudulent transactions without the knowledge of employees 3 4 6 .
Attacks on off-chain systems—servers and internal company processes—are harder to protect than smart contracts, so attackers have switched to this more profitable and less controllable attack vector 12 .
Theft of private keys and seed phrases through hacking of user devices and phishing remains a significant loss factor 2 .

What new vulnerabilities have appeared in smart contracts in 2025

In 2025, new vulnerabilities and operational risks have been identified and continue to emerge in the field of smart contract security on blockchains, among which the following key categories stand out:

Vulnerabilities related to memory overuse and uninitialized variables, which can lead to leaks of critical information and unpredictable behavior of contracts. Such errors are allowed in the logic of working with memory and variables inside contracts, which gives attackers a chance to gain access to private data or change the course of transactions 1 .
A classic and still relevant reentrancy vulnerability, in which an external call to a smart contract is made before the state update is complete, allowing an attacker to repeatedly retry transactions and withdraw funds. Although this type of attack was first widely discovered back in 2016 (in the DAO), in 2025 it remains one of the most studied and dangerous classes of vulnerabilities, especially if developers do not use modern mitigation techniques 1 4 .
Economic vulnerabilities, such as transaction order manipulation (MEV attacks): Attackers can influence the order of transactions in a block, which allows them to extract additional profit, as well as influence the execution of contracts 1 .
Problems with the generation and predictability of random numbers used inside smart contracts for cryptographic operations or game mechanics. Inadequate random number generation makes the system vulnerable to prediction and manipulation of results 1 .
New types of vulnerabilities that are associated with the features of popular blockchain platforms (Ethereum, Binance Smart Chain and others), as well as with the use of open source Web3 code, which often contains errors or exploitable defects, making such contracts potential targets for attacks 5 6 .
In 2025, the use of artificial intelligence and autonomous agents continues to grow, which also poses a new challenge in detecting and preventing smart contract exploits. At the same time, research is emerging to block illegal activities programmatically, but these technologies are in their early stages of development 9 .

In conclusion, it can be noted that vulnerabilities in smart contracts in 2025 are both classic errors in logic and security, and new threats associated with economic attacks and random number generation, as well as with the peculiarities of the development of the Web3 ecosystem and the use of AI. To protect against them, a comprehensive audit, modern analysis tools and constant updating of security practices are necessary 1 4 5 .

Let’s look at a selection of articles that reveal methods for hacking crypto exchanges in 2025 and the main cyber threats in the crypto industry:

“The 8 Biggest Crypto Hacks in History” – An overview of the biggest hacks and attack methods on crypto exchanges, including types of attacks on bridges, wallets and exchanges, with a description of phishing and social engineering mechanisms. (Kaspersky)[web
“Hackers stole $2 billion from crypto services in 2025” — an analytical article about the largest hacks, including the $1.5 billion Bybit hack, with an emphasis on technical and social attacks, as well as insider threats and smart contract vulnerabilities. (RBC)[web
“Coinbase Hack: How Hackers Stole Data of 70,000 Customers” – details of the cyberattacks on Coinbase using social engineering on employees and further consequences for users. (Bithide) 3
“How Crypto Exchanges Are Being Hacked in 2025” – LinkedIn analytics on typical methods such as third-party attacks, deepfake, and attacks on DeFi smart contracts with examples. 4
“Cyber Threats to Crypto Business. Trends 2024–2025” — an article about modern attack methods, including interface substitution and sophisticated social engineering. 5
“Hackers stole $2.17 billion in cryptocurrency in 2025” – a review of the largest thefts, focusing on the Bybit hack and other large-scale incidents. (Expert.ru)[web:These materials will help you better understand the current threats and protection methods in the crypto industry in 2025.

What are the biggest crypto hacks since 2022?

Biggest crypto hacks since 2022:

Ronin Network hack (March 2022) – theft of approximately $615 million in Ethereum and USDC. The attack occurred due to the compromise of network nodes of a cross-chain bridge. The hack was reportedly carried out through social engineering methods against members of the Axie Infinity project team 1 2 .
Binance hack (October 2022) – hackers exploited a vulnerability in the BNB Chain cross-chain bridge, creating additional BNB tokens and withdrawing around $570 million, which led to the blockchain stopping and serious losses 1 2 .
FTX hack (2022-2023) – after the exchange went bankrupt, over $600 million in cryptocurrency went missing, and in January 2023, there was an additional incident with the theft of $15 million 1 2 .
Bybit hack (February 2025) – the largest hack in the history of the crypto market, worth about $1.4 billion. The attackers gained control of a cold wallet where Ethereum was stored 2 3 .
Wormhole hack (February 2022) – $325 million stolen via cross-chain bridge attack, lost funds partially recouped through third-party investment 1 2 .
In 2025, the largest crypto hack in history occurred on the Chinese Bitcoin pool LuBian with the loss of up to $14 billion, one of the largest hacks of crypto assets in the world 9 .

These cases show that the main targets of attacks remain vulnerabilities in cross-chain bridges, hot and cold wallet infrastructure, and human factors (social engineering). In addition to technical vulnerabilities, major hacks are caused by sophisticated attacks and the activities of hacker groups, including those associated with states 1 2 .

What were the characteristics of the biggest hacks after 2022?

The characteristics of the largest crypto hacks after 2022 are as follows:

Social engineering and employee compromise have become the primary entry point into infrastructure, as seen in the Ronin Network and CoinDCX attacks. Attackers use personal contacts, phishing emails, and even job offers to gain access to private data and internal systems 1 2 .
Attacks on cross-chain and decentralized finance (DeFi) bridges continue to be vulnerable. Vulnerabilities in contract logic or key management have allowed hundreds of millions of dollars to be stolen. Examples include the Wormhole hack in 2022 and the Binance Bridge 2 .
The use of sophisticated data and interface substitution techniques, including deepfakes and multi-signature wallets, complicates the detection of attacks and allows funds to be withdrawn from trusted accounts 1 .
The rise of ransomware and spyware is creating an additional layer of threats, especially for the corporate infrastructure of crypto exchanges and related services. Attacks on companies’ IT infrastructure are causing disruptions and data leaks 1 4 .
Hacking is often accompanied by large-scale leaks of customer data, which puts not only funds but also the personal safety of users at risk 2 .
The largest attacks in recent years demonstrate a trend towards coordinated activity by large hacker groups using modern tools, including malware, zero-day vulnerabilities, and methods of closed access to systems through compromised accounts 1 3 .

Thus, the main feature of attacks after 2022 is the combination of classic vulnerabilities (phishing, bridging attacks, re-entry) with new social engineering methods and technical innovations of hackers, which requires complex and multi-layered security measures.

In March 2022, one of the largest hacks in the history of the crypto industry occurred — an attack on the Ronin Network blockchain network, associated with the Axie Infinity project. As a result, the attackers stole about $615 million in Ethereum and USDC, exploiting a vulnerability in the network’s validator nodes. Ronin operated as an Ethereum sidechain and supported cross-chain bridges, allowing users to transfer tokens between different blockchains.

The essence of the attack was to compromise several validator nodes – to confirm transactions in Ronin, a minimum of five signatures from nine validators were required. However, the hackers managed to gain control over the private keys of four of them, and one validator belonged to Axie DAO, which the attackers used to obtain a signature to carry out fraudulent withdrawals.

The attack was carried out by exploiting a gasless RPC node, which became a backdoor in the transaction verification system. It was thanks to these flaws that a series of fraudulent transactions were carried out, allowing huge amounts of cryptocurrency to be stolen. The loss of funds was discovered a week later, after a user failed to withdraw 5 thousand ETH through the Ronin bridge.

In response to the hack, the Ronin team temporarily suspended the Ronin Bridge and the Katana decentralized platform, and expanded the number of required consents for withdrawals from five to eight validators. Law enforcement agencies were involved in the investigation, and the company’s specialists continued their efforts to return the stolen funds. However, a significant portion of the stolen assets remained immobile at the addresses of the attackers.

The incident highlighted the dangers of reducing the number of validators in order to increase network capacity, which has led to a decrease in security. It also highlights the risks of cross-chain bridges, which are considered prime targets for hackers due to the difficulty of comprehensively protecting them.

The Ronin Network hack is not an isolated incident in 2022–2025. Similar large-scale attacks, such as those on Binance and Wormhole, show the demand for vulnerabilities in cross-chain bridges and hot and cold wallets. An even larger-scale hack was the Bybit hack in February 2025, amounting to approximately $1.4 billion, when attackers gained control of a cold wallet.

Overall, this series of successful attacks demonstrates that despite technical progress and the efforts of development teams, the crypto industry remains vulnerable to complex and sophisticated hacker methods – combining technical vulnerabilities and the use of the human factor (social engineering). The high risk is associated with the need to balance transaction speed, user convenience and ensuring multi-layered infrastructure security.

Thus, studying such details of hacks is critical for further protection of projects, development of effective security mechanisms and prevention of such large-scale losses in the future.

Why Cross-Chain Bridges Remain the Crypto Industry’s Top Hacker Target

Cross-chain bridges remain a prime target for hackers in the crypto industry for a number of objective reasons related to their architecture, operating methods, and vulnerabilities.

First, cross-chain bridges act as intermediaries between different blockchains, allowing crypto assets to be transferred from one chain to another. These are essentially complex protocols that lock the original tokens on one blockchain and issue “wrapped” versions of those assets on another. When the transition is reversed, the wrapped tokens are “burned” and the original tokens are unlocked. This multi-step scheme requires coordination and confirmation of multiple transactions between different systems and involves key participants called validators or oracles 1 5 .

Secondly, it is in the places where transactions are stored and confirmed that critical vulnerabilities are concentrated. For example, many bridges use centralized storage or multi-signatures with a limited number of validators. Taking control of some of these validators (as happened during the Ronin Network hack, where attackers gained control of 5 out of 9 validators) or compromising keys gives hackers the opportunity to authorize fraudulent transactions and withdraw funds unnoticed 1 2 .

Third, deposit and transaction verification checks are often implemented with vulnerabilities that allow for the creation of false deposit events or bypassing the underlying asset locking mechanisms. These holes were exploited in the Wormhole and Qubit Finance attacks, where the logic for verifying digital signatures and asset deposits was compromised 1 .

Fourth, the anonymity and pseudonymity of blockchain transactions make it difficult to track funds transferred across bridges. Hackers often use bridges to move stolen assets between chains, making it difficult for law enforcement and regulators to identify and recover stolen assets 1 2 .

Fifth, cross-chain bridges remain technologically experimental systems, with many processes still not fully debugged and code not always subject to comprehensive audit. This creates a fertile environment for new vulnerabilities and exploits to emerge 5 .

Taken together, these factors make cross-chain bridges an attractive target for hackers. According to analysts, over $2 billion has been stolen through attacks on cross-chain bridges since the beginning of 2022 — approximately 70% of all stolen funds in the crypto market during this period. The main problem is the presence of a “single point of failure” in the bridges in the form of centralized or limited key management and insufficient verification of transactions for authenticity 3 .

Thus, until cross-chain bridges reach a more mature level of security with distributed trust and multi-stage verification of transactions, they will remain a major vulnerability in the blockchain ecosystem and a target for hackers 1 2 3 .

How Bridge Code Bugs Allow Attackers to Create Fake Assets

Bugs in the cross-chain bridge code create opportunities for attackers to generate counterfeit assets by violating the logic of transaction authentication and errors in handling deposits and issuance of “wrapped” tokens. The essence of the cross-chain bridge process is that assets are locked in the source chain, and equivalent tokens (wrapped tokens) are issued in the target network, which can then be used. After the reverse transfer, the wrapped tokens are burned and the original ones are unlocked.

The main bugs that allow the creation of fake assets:

Violating real deposit verification and creating false events. If the bridge smart contract receives unverified or fake deposit data, it can issue tokens without actually locking the assets in the original chain. This allows attackers to “fake” tokens that are not backed by real assets 1 4 .
Errors in the logic of multi-signatures and key management. Centralized or partially centralized bridges with a limited number of validators are vulnerable to key compromise. By gaining control over some of the signatures, hackers can legitimize the issuance of tokens without locking up funds, essentially creating them “out of thin air” 1 2 .
Bugs or flaws in the code, such as problems with reentrancy handling, arithmetic errors, or logic errors that allow the token issuance function to be retried or restrictions to be bypassed. Crypto code cannot be easily fixed on the fly, so bugs remain relevant until the next update and are susceptible to exploitation 2 .
Incorrect integration with oracles and third-party components that provide data on the state of blockchains. If an oracle provides false information, the bridge may mistakenly believe that assets are locked and issue tokens without collateral 2 .
Exploitation of bugs in user interfaces and APIs that allow attackers to forge transaction data and run token issuance functions with empty or invalid input parameters 1 .

Ultimately, such vulnerabilities allow the creation of non-existent assets, which leads to token inflation in the target network, loss of user trust, and often to large financial losses. Eliminating such problems requires a comprehensive audit of smart contract code, formal verification of logic, multi-level transaction confirmation, and the use of distributed key management mechanisms.

Thus, bugs in bridge code are not just technical errors, but factors that directly affect the integrity and security of multi-chain interactions in blockchains, making them a priority for the entire crypto ecosystem 1 2 4 .

What specific vulnerabilities in bridge code allow fake assets to be created

Specific vulnerabilities in cross-chain bridge code that allow attackers to create counterfeit assets include the following main types:

Weak on-chain validation. Many bridges perform minimal verification of transactions on the blockchain and offload the bulk of the transaction verification logic to centralized servers. If a smart contract does not sufficiently verify signatures or access levels, an attacker can forge or tamper with asset locking proofs, allowing a new issue of wrapped tokens to be created on a different blockchain. For example, if a Merkle tree is used for transaction proofs, it is possible to forge these proofs and bypass the security 1 .
Weak off-chain validation. Back-end servers that process deposit transaction hashes may treat fake or malicious transactions as valid if they do not verify the initiator addresses or hash structure. This allows attackers to submit false hashes to the server and obtain permission to issue tokens without actually depositing funds 1 .
Misconfiguration and security errors. Changing parameters such as acceptable signers, whitelisted addresses, or message verification standards can cause all messages to be automatically allowed, regardless of their legitimacy. This situation has allowed hackers to successfully bypass verification and release fake assets, as was the case in the famous bridge protocol update before the hack 1 .
Logical bugs in smart contracts. For example, errors in reentrancy functions, incorrect calculation of balances, incorrect handling of transaction states – all this creates opportunities for fraudulent operations, including re-issuance of tokens 1 2 .
Vulnerabilities in integration with external components such as oracles. If an oracle provides false information about the asset lock status, the bridge may assume that funds have been deposited and issue equivalent tokens without real collateral 1 .

All of these vulnerabilities together allow attackers to create counterfeit assets by “generating” tokens that are not backed by real cryptocurrencies, which disrupts the integrity of the blockchain economy and leads to major financial losses for users and platforms.

Protecting against such attacks requires a comprehensive approach that includes thorough code auditing, improved on-chain and off-chain validation, proper configuration of security parameters, and the use of multi-level authentication and transaction confirmation mechanisms 1 .