CVE-2026-106374 in Chrome
Summary
by MITRE • 10/07/2026
Type confusion in V8 in Google Chrome prior to 155.0.8059.39 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Low)
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Analysis
by VulDB Data Team • 10/07/2026
The vulnerability identified as a type confusion issue within the V8 JavaScript engine, which powers Google Chrome prior to version 155.0.8059.39, represents a critical memory safety flaw that can be leveraged by remote attackers to achieve arbitrary code execution. Type confusions occur when an application incorrectly interprets the data type of a variable or object in memory, leading to operations being performed on data structures as if they were a different type. In the context of V8, this typically involves the engine's Just-In-Time compiler misidentifying the shape or properties of JavaScript objects during optimization phases. When such a mismatch occurs, it can result in out-of-bounds reads or writes, allowing an attacker to read sensitive memory contents or overwrite critical data structures with malicious payloads. This specific instance was classified by Chromium as having low security severity, likely due to mitigating factors present in the browser's architecture at that time, but it remains a significant risk for exploitation via crafted HTML pages served from untrusted sources.
From an operational perspective, this vulnerability allows a remote attacker to execute arbitrary code inside the sandboxed environment of the browser. Modern browsers employ multiple layers of security isolation, including site isolation and process separation, to limit the impact of successful exploits. However, type confusion vulnerabilities in V8 have historically been potent vectors for breaking out of these sandboxes through techniques such as heap spraying or exploiting specific object layouts to gain control over execution flow. An attacker could craft a malicious HTML page containing JavaScript that triggers this type confusion, causing the browser to execute arbitrary machine code with the privileges of the current user. This can lead to full system compromise if combined with additional exploitation steps designed to escape the sandbox boundary, although the low severity rating suggests that such an escape might be difficult or require further vulnerabilities in conjunction with this flaw.
The technical root cause lies in the complex interaction between V8's type inference mechanisms and its optimization pipelines. When JavaScript code is executed, V8 attempts to optimize performance by assuming certain types remain consistent throughout execution. If a crafted script manipulates object properties in a way that violates these assumptions without proper runtime checks or deoptimization triggers, the engine may proceed with optimized code paths that rely on incorrect type information. This discrepancy can lead to memory corruption where pointers are dereferenced incorrectly, potentially pointing to attacker-controlled data rather than intended objects. Such flaws align closely with CWE-843, which describes access of a variable to incorrect memory location due to misinterpretation of its type, and often facilitate exploitation techniques categorized under MITRE ATT&CK tactics such as Initial Access via crafted content or Execution through script interpretation within the browser environment.
Mitigation strategies for this vulnerability primarily involve ensuring that all instances of Google Chrome are updated to version 155.0.8059.39 or later, where the underlying type checking logic in V8 has been patched to prevent the misinterpretation of object types during optimization. Users should enable automatic updates to ensure timely application of security patches as they become available. Additionally, organizations can enforce strict content security policies and restrict the execution of untrusted JavaScript within their environments to reduce the attack surface. While browser sandboxing provides a robust defense-in-depth layer, relying solely on it is insufficient given the sophistication of modern exploit chains. Regular auditing of third-party extensions and disabling unnecessary features like NPAPI plugins further reduces the likelihood of successful exploitation by limiting the available vectors for code injection and execution within the vulnerable component.