CVE-2025-7656 in Chrome
Summary
by MITRE • 07/15/2025
Integer overflow in V8 in Google Chrome prior to 138.0.7204.157 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 07/16/2025
The vulnerability identified as CVE-2025-7656 represents a critical integer overflow condition within the V8 JavaScript engine used by Google Chrome and Chromium-based browsers. This flaw exists in versions prior to 138.0.7204.157 and manifests as a heap corruption vulnerability that can be exploited remotely through maliciously crafted HTML content. The issue stems from improper handling of integer arithmetic operations within the engine's memory management subsystem, creating opportunities for attackers to manipulate memory layout and execute arbitrary code. The Chromium security severity rating of High indicates the significant risk this vulnerability poses to user systems and browser security.
The technical root cause of this vulnerability lies in the V8 engine's handling of integer values during memory allocation operations. When processing certain JavaScript operations involving large integer values, the engine fails to properly validate or constrain integer arithmetic, leading to overflow conditions that can result in unexpected memory layout changes. This integer overflow specifically affects heap memory management where the engine calculates buffer sizes or memory allocation requirements based on user-supplied JavaScript values. The flaw allows an attacker to manipulate these calculations such that the resulting memory allocation becomes insufficient or excessive, creating heap corruption conditions that can be leveraged for code execution. This type of vulnerability falls under CWE-190, which specifically addresses integer overflow conditions in software systems.
The operational impact of CVE-2025-7656 extends beyond simple browser exploitation to encompass potential system compromise and data theft. Remote attackers can craft HTML pages containing malicious JavaScript code that triggers the integer overflow condition when processed by vulnerable Chrome versions. Upon successful exploitation, attackers gain the ability to execute arbitrary code within the browser's sandboxed environment, potentially leading to full system compromise. The heap corruption can be used to overwrite critical memory structures, manipulate function pointers, or inject malicious code into the browser process. This vulnerability directly aligns with ATT&CK technique T1059.007 for JavaScript and VBScript execution, while also mapping to T1068 for local privilege escalation through memory corruption exploits. The attack surface is particularly concerning as it requires no user interaction beyond visiting a malicious webpage, making it a prime candidate for drive-by download attacks.
Mitigation strategies for CVE-2025-7656 primarily focus on immediate browser updates to versions 138.0.7204.157 or later where the vulnerability has been patched. Organizations should implement comprehensive patch management protocols to ensure all Chrome installations are updated promptly, as the vulnerability can be exploited through social engineering or compromised websites. Browser hardening measures such as enabling sandboxing features, disabling unnecessary JavaScript capabilities, and implementing content security policies can provide additional defense layers. Network-based mitigations including web application firewalls and content filtering systems can help detect and block malicious HTML content. Security monitoring should focus on detecting unusual JavaScript execution patterns or memory allocation behaviors that might indicate exploitation attempts. The vulnerability's classification as a heap corruption issue also necessitates regular memory integrity checks and endpoint detection systems that can identify suspicious memory modifications. Organizations should also consider implementing browser isolation techniques and zero-trust network architectures to limit potential damage from successful exploitation attempts.