CVE-2026-102328 in Chrome
Summary
by MITRE • 09/29/2026
Type confusion in V8 in Google Chrome prior to 154.0.8037.92 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 09/29/2026
The vulnerability identified as a type confusion issue within the V8 JavaScript engine, which powers Google Chrome prior to version 154.0.8037.92, represents a critical failure in memory safety and runtime type checking mechanisms. Type confusions occur when an application incorrectly assumes that a variable or object holds one data type while it actually contains another. In the context of V8, this typically involves the engine misinterpreting the structure or properties of JavaScript objects during execution. When such a confusion is triggered by a crafted HTML page hosted on a malicious website, it allows for arbitrary memory reads and writes outside the intended boundaries of the object in question. This specific flaw was classified with high severity by Chromium security teams due to its potential to bypass sandboxing protections and lead directly to remote code execution.
From a technical perspective, V8 relies heavily on hidden classes or shapes to optimize property access and method calls for JavaScript objects. These internal structures map out the layout of object properties in memory to enable fast lookups without dynamic type checking at runtime. A type confusion vulnerability arises when an attacker can manipulate these internal representations so that V8 treats a pointer as one data structure while it is actually another, such as treating a small integer array element as a heap pointer or vice versa. This mismatch allows the attacker to craft payloads that exploit the misinterpreted memory layout to write arbitrary values into controlled locations in the process memory space. Because JavaScript execution occurs within a sandboxed environment designed to restrict access to system resources and other processes, successfully exploiting this flaw requires breaking out of that isolation layer through precise heap manipulation techniques.
The operational impact of this vulnerability is severe because it enables remote code execution with the privileges of the browser process. An attacker can construct a malicious webpage containing specially crafted JavaScript code that triggers the type confusion when rendered by V8. Upon visiting this page, potentially without any user interaction beyond loading the content, the exploit chain executes arbitrary commands on the victim's machine. This could lead to full system compromise, including data theft, installation of malware, or use of the device as part of a botnet. The ability to execute code inside the sandbox is particularly dangerous because it undermines one of the primary defense-in-depth strategies employed by modern browsers, which rely heavily on process isolation and sandboxing to limit the blast radius of web-based attacks.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-843, which describes access to incorrect type during interpretation or casting operations. It also maps closely to MITRE ATT&CK techniques related to initial exploitation via browser vulnerabilities, specifically those involving memory corruption and sandbox escape mechanisms such as T1205 Trust Distribution Techniques or more broadly the execution of malicious code through web-based vectors like T1189 Drive-by Compromise. The exploit chain likely involves additional stages including information disclosure to locate heap structures, followed by arbitrary read-write primitives derived from the type confusion, ultimately leading to control flow hijacking or direct shellcode injection within the browser process context.
Mitigation strategies primarily involve updating Google Chrome and its underlying V8 engine to version 154.0.8037.92 or later, where these specific memory safety checks have been reinforced. Developers should ensure that automatic update mechanisms are enabled for all browsers in use across organizational endpoints to minimize the window of exposure. For users unable to patch immediately, employing browser hardening techniques such as disabling JavaScript execution on untrusted sites via enterprise policies can reduce risk significantly. Additionally, deploying endpoint detection and response solutions capable of monitoring for anomalous memory access patterns or suspicious child process creation from browser binaries may help detect exploitation attempts in real time before full system compromise occurs.