CVE-2026-119262 in Chrome
Summary
by MITRE • 10/30/2026
Improper input validation in V8 in Google Chrome prior to 156.0.8078.79 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/30/2026
The vulnerability identified as an improper input validation flaw within the V8 JavaScript engine, which powers Google Chrome prior to version 156.0.8078.79, represents a significant risk to browser-based security postures. This specific defect allows for potential arbitrary code execution inside the sandboxed environment when a user interacts with a maliciously crafted HTML page. The core technical issue stems from insufficient checks on input data processed by V8 during script compilation or interpretation phases. When an attacker constructs a specially designed web page containing malformed JavaScript objects, arrays, or type conversions, they can trigger undefined behavior within the engine's internal memory management structures. This lack of rigorous boundary checking enables the manipulation of heap metadata or pointer values, leading to conditions such as use-after-free scenarios or out-of-bounds writes that bypass standard safety mechanisms inherent in modern browser architectures.
From a technical perspective, this flaw aligns closely with CWE-20 Improper Input Validation and often manifests through vulnerabilities categorized under CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer. The V8 engine is responsible for parsing, compiling, and executing JavaScript code efficiently. When input validation fails during these processes, particularly in complex scenarios involving typed arrays or WebAssembly integration points, it creates an opportunity for memory corruption. An attacker exploits this by crafting HTML content that forces the browser to process specific sequences of operations designed to corrupt internal data structures. Because V8 operates within a sandboxed context to isolate web content from the host operating system, successful exploitation requires chaining multiple vulnerabilities or leveraging edge cases in type handling logic to escape these restrictions and achieve arbitrary code execution with the privileges of the compromised user account.
The operational impact of this vulnerability is severe due to its remote exploitability vector. Since it can be triggered simply by visiting a malicious website hosted on any server controlled by an adversary, there is no requirement for physical access or prior authentication beyond standard web browsing activities. This characteristic places it firmly within the MITRE ATT&CK framework under techniques such as T1059 Command and Scripting Interpreter, specifically JavaScript execution, and potentially T1203 Exploitation for Client Execution if combined with other social engineering tactics to lure users into visiting the payload site. Successful exploitation could lead to full system compromise, allowing attackers to install malware, exfiltrate sensitive data stored in browser cookies or local storage, hijack user sessions, or use the compromised machine as part of a botnet. The high severity rating assigned by Chromium security reflects the ease with which this flaw can be weaponized and its potential to bypass modern defense-in-depth strategies like sandboxing if not properly mitigated through rigorous input sanitization.
Mitigation for this vulnerability primarily involves immediate software updates rather than configuration changes, as it resides within the core browser engine itself. Users running versions of Google Chrome prior to 156.0.8078.79 must upgrade to the patched version where developers have implemented stricter validation checks and enhanced memory safety features within V8. Organizations should enforce automated patch management policies to ensure rapid deployment of security updates across all endpoints. Additionally, while not a direct fix for this specific engine flaw, employing browser hardening techniques such as disabling JavaScript in untrusted sites via enterprise policy configurations or using extensions that restrict script execution can provide an additional layer of defense against exploitation attempts. Security teams should also monitor network traffic for indicators of compromise associated with drive-by download attacks and ensure that endpoint detection and response solutions are updated to recognize patterns consistent with V8-based exploit kits targeting this specific vulnerability class.