Description

Type confusion in V8 in Google Chrome prior to 152.0.7977.65 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-25T21:17:49.610Z",
  "pubdate": "2026-08-25T21:17:49.610Z",
  "executiveSummary": "A critical type confusion vulnerability has been identified within the V8 JavaScript engine utilized by Google Chrome.\nThe flaw allows a remote attacker to achieve arbitrary code execution within the browser's sandbox environment by leveraging a specially crafted HTML page.\nThis vulnerability specifically affects Google Chrome versions prior to 152.0.7977.65.\nType confusion occurs when the V8 engine fails to correctly validate the data type of an object, leading the engine to interact with memory as if it were a different, incompatible type.\nSuccessful exploitation grants an attacker the ability to bypass security boundaries, potentially resulting in unauthorized code execution, arbitrary memory reads or writes, and compromise of the browser's internal data structures.\nDue to the nature of web-based delivery, this vulnerability is highly exploitable via drive-by download or social engineering, as it requires only that a user visits a malicious website.\nGiven the high severity rating by the Chromium project, immediate patching is required to mitigate the risk of browser compromise and sandbox escape.",
  "technicalDetails": "The vulnerability resides within the V8 engine's Just-In-Time (JIT) compilation or object handling logic, where a type confusion flaw allows an attacker to manipulate object properties or types in a way that violates internal type safety guarantees.\nAt its core, V8 utilizes hidden classes and shape-based optimizations to speed up property access. A type confusion occurs when the engine is tricked into believing a memory location contains an object of type A, while it actually contains an object of type B.\nThe attack flow typically involves the manipulation of JavaScript arrays or objects to trigger an out-of-bounds access or a type mismatch during optimized code execution (e.g., in the TurboFan compiler). By force-triggering speculative optimization, an attacker can coerce the JIT compiler to emit machine code that treats a floating-point array's backing store as a pointer or an object reference.\nOnce the type confusion is successfully triggered, the attacker gains a primitive that allows for arbitrary read and write access to the renderer process's memory space. Because this occurs inside the V8 heap, an attacker can overwrite function pointers, return addresses, or JavaScript object structures to redirect execution flow to attacker-controlled shellcode or perform Return-Oriented Programming (ROP).\nThis vulnerability does not require authentication or elevated user privileges; the exploitation is triggered via standard web interaction. Once the process memory is corrupted, the attacker can execute arbitrary machine code within the context of the renderer process. While this code runs within the Chromium sandbox, further exploits could theoretically be chained to escape the sandbox or access sensitive user data residing in the process.\nThe vulnerability affects all Google Chrome installations prior to 152.0.7977.65, specifically impacting the V8 component's handling of memory objects. The root cause is a failure in the static analysis or dynamic type checking mechanisms within the V8 engine, which allows for the creation of an inconsistent state between the expected and actual layout of object memory. An attacker facilitates this by delivering a malicious HTML document containing crafted JavaScript code designed to induce this memory state mismatch during V8's optimization lifecycle."
}