Binance hack amount reaches $6.3B as security questions arise

Following a significant security incident, the Binance hack amount has been reported at $6.3 billion, leaving industry observers and users seeking clarity on how the exchange manages its digital assets. The breach, which affected the exchange’s own hot wallet, has raised questions about the internal safeguards intended to limit unauthorized access to funds.

Binance co-CEO Richard Teng stated on Oct. 30 that the incident primarily impacted the company's hot wallets, noting that the majority of customer assets are maintained in offline cold storage. These assets are typically moved to hot wallets only when users initiate withdrawal requests. However, the $6.3 billion figure represents the cumulative value of assets affected across 10 different blockchains. On the Ethereum network, attackers were able to repeatedly drain a hot wallet as new deposits were processed.

Blockchain records show funds moving but cannot confirm the internal controls governing those specific transfers.

Understanding the Binance hack news and security

In an initial report released Tuesday, Binance disclosed that attackers gained access to an internal wallet-signing service, allowing them to move funds outside of the standard withdrawal process. The exchange noted that certain technical details would remain confidential to prevent further exploitation. While some industry experts suggest that holding billions in hot wallets is not inherently unusual for an exchange of Binance’s scale, the incident has highlighted the complexities of custody arrangements.

Jonathan Riss, an analyst at CertiK, explained that public blockchain records can track the movement of funds but fail to provide insight into the internal signing architecture or transaction limits that govern those transfers. Riss noted that if attackers obtain valid signatures, their potential access is dictated by the limits enforced by the signing system rather than the wallet's balance at any single moment. Other experts, including Fireblocks co-founder Idan Ofrat, noted that exchanges generally keep only enough funds in hot wallets to cover a few days of expected withdrawals.

While rivals such as Coinbase, Gate, and Upbit have disclosed their cold-storage ratios following the event, Binance did not respond to inquiries regarding its specific wallet balances and security protocols. BitGo chief product officer Eugene Hahr stated that the breakdown of custody arrangements remains a question that Binance is best positioned to address.

Why it matters

This incident underscores the difficulty of assessing the security posture of centralized exchanges from an external perspective. Because internal signing architecture and authorization processes are rarely public, users and industry analysts struggle to verify how exchanges protect against compromised systems. The event highlights the critical need for robust, independent transaction limits that remain effective even if an application requesting a signature is breached.