CVE-2026-85046 in Chrome
Summary
by MITRE • 09/03/2026
Type confusion in V8 in Google Chrome prior to 152.0.7977.82 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 • 09/03/2026
The vulnerability identified as a type confusion flaw within the V8 JavaScript engine of Google Chrome prior to version 152.0.7977.82 represents a critical failure in memory safety and runtime type checking mechanisms. Type confusion vulnerabilities occur when an application incorrectly interprets the data type of a variable or object, leading to operations being performed on incompatible types. In the context of V8, this typically involves the Just-In-Time (JIT) compiler optimizing code based on assumed types that are later invalidated by dynamic changes in JavaScript execution flow. When such assumptions break down due to crafted input, the engine may access memory locations with incorrect offsets or sizes, allowing an attacker to read from or write to arbitrary memory addresses outside the intended scope of the object. This specific flaw was classified as High severity within the Chromium security framework, indicating a significant risk that could lead to full system compromise if exploited successfully in a targeted attack scenario.
The operational impact of this vulnerability is severe because it enables remote code execution (RCE) inside the browser sandbox. Modern browsers employ multiple layers of defense-in-depth, including sandboxing processes to limit the damage caused by successful exploits. However, type confusion bugs often provide the necessary primitives for an attacker to bypass these protections through techniques such as arbitrary read and write operations. By carefully crafting a malicious HTML page that triggers the type confusion state, an attacker can manipulate memory structures like heap metadata or function pointers. This manipulation allows the execution of arbitrary shellcode within the context of the browser process. While sandboxing restricts access to sensitive system resources, achieving code execution inside the sandbox is often sufficient for further exploitation steps, such as escaping the sandbox via a secondary vulnerability or stealing user credentials and session tokens stored in memory.
From a technical classification perspective, this flaw aligns with CWE-843, which refers to Access of Incorrect Type, and more broadly falls under CWE-120 Buffer Overflow if it leads to out-of-bounds writes during the misinterpretation of data types. In terms of offensive security frameworks, this vulnerability facilitates techniques associated with MITRE ATT&CK Tactic TA0004 Privilege Escalation and specifically relates to sub-techniques involving memory corruption exploitation. The attack vector is classified as Remote (ATT&CK T1190), meaning the attacker does not need physical or local access to the target system but can trigger the exploit via a web page visited by the user. This highlights the importance of browser security in mitigating drive-by download attacks and malicious script execution scenarios commonly found on compromised websites or phishing campaigns.
Mitigation for this vulnerability primarily relies on applying the official patch provided by Google Chrome, which updates the V8 engine to version 152.0.7977.82 or later. These patches typically include rigorous type checking improvements and fixes in the JIT compiler logic that prevent the misinterpretation of object types during execution. For organizations managing large fleets of devices, automated patch management systems should be configured to prioritize browser updates due to the high prevalence of this attack vector. Additionally, users can employ security best practices such as keeping browsers updated automatically, using extensions that block malicious scripts or known exploit kits, and enabling sandboxing features where available. Security monitoring tools may also look for indicators of compromise related to unusual memory access patterns or attempts to execute code from non-executable regions within browser processes, although detection at this level requires advanced endpoint protection capabilities capable of analyzing runtime behavior rather than just static signatures.