CVE-2026-91726 in Chrome
Summary
by MITRE • 09/16/2026
Out of bounds read in WebGL in Google Chrome on on Android prior to 153.0.8010.47 allowed a remote attacker to read memory outside the sandbox via a crafted HTML page. (Chromium security severity: Critical)
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Analysis
by VulDB Data Team • 09/16/2026
The vulnerability identified as an out-of-bounds read within the WebGL implementation of Google Chrome on Android represents a critical security flaw that compromises the integrity of the browser's isolation mechanisms. This issue stems from improper boundary checks during the processing of graphics commands, specifically when handling shader programs or texture operations via JavaScript interfaces exposed to web content. When a remote attacker crafts an HTML page containing maliciously constructed WebGL calls, they can trigger memory access patterns that exceed the allocated buffer limits. Because this operation occurs within the renderer process, which is responsible for executing untrusted web content, the flaw allows data from adjacent memory regions to be read and potentially returned to the JavaScript context or used in subsequent computations.
The operational impact of this vulnerability is significant due to its potential to bypass Chrome's sandboxing architecture. The browser relies on strict separation between privileged processes that handle sensitive user data and untrusted renderer processes that execute web pages. An out-of-bounds read, while not directly allowing arbitrary code execution like a buffer overflow might, provides the attacker with a mechanism for information disclosure. By carefully analyzing the memory contents returned through the WebGL API or side channels associated with graphics processing units, an attacker can potentially leak sensitive information such as cryptographic keys, session tokens, or other data residing in adjacent heap allocations. This capability undermines the fundamental trust model of modern web browsers and poses a severe risk to user privacy and security.
From a classification perspective, this vulnerability aligns with CWE-125, which describes out-of-bounds read errors where software reads past the end of a buffer or array. In the context of browser exploitation techniques, it maps closely to ATT&CK technique T1074, specifically data staged in remote locations or local staging for exfiltration purposes, although the primary vector here is memory disclosure rather than file system manipulation. The severity rating of Critical by Chromium security teams reflects the high likelihood of successful exploitation and the potential for significant data leakage without requiring user interaction beyond visiting a malicious webpage.
Mitigation strategies primarily involve updating to Google Chrome version 153.0.8010.47 or later on Android devices, as this release contains patches that enforce stricter bounds checking within the WebGL pipeline. Developers integrating third-party libraries should ensure they are using versions free from known vulnerabilities and consider implementing Content Security Policy headers to restrict inline scripts and potentially limit the impact of such exploits by reducing the attack surface for arbitrary code execution. Additionally, users should maintain up-to-date operating systems and browser software to benefit from continuous security improvements and patch deployments that address these low-level memory safety issues in complex rendering engines.