CVE-2026-93385 in Chrome
Summary
by MITRE • 09/18/2026
Information leak in Paint in Google Chrome prior to 153.0.8010.52 allowed a remote attacker to obtain sensitive information via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 09/18/2026
The vulnerability identified as an information leak within the paint subsystem of Google Chrome represents a significant breach in browser isolation and data confidentiality mechanisms. This flaw existed in versions prior to 153.0.8010.52 and stemmed from improper handling of graphical rendering operations, specifically those related to how canvas elements or other painting contexts managed memory allocation and state persistence during complex drawing sequences. When a remote attacker crafted an HTML page designed to trigger specific edge cases within the browser's graphics pipeline, they could exploit race conditions or insufficient boundary checks in the paint routine. This allowed for the reading of memory contents that should have been isolated from web content, effectively bypassing standard security boundaries such as same-origin policies and sandbox restrictions intended to prevent cross-site data theft.
From a technical perspective, this issue aligns with CWE-200, which categorizes information exposure vulnerabilities where sensitive system or application data is accessible to unauthorized actors without explicit authorization. The attack vector relies on the browser's internal state management during rendering processes, where temporary buffers containing potentially sensitive data from previous operations or other tabs were not properly cleared or protected before being reused or exposed through side-channel effects in the graphics output. By manipulating DOM elements and CSS properties to force specific painting behaviors, an attacker could induce the browser to expose memory leaks that reveal internal state information, such as cookies, session tokens, or previously rendered content from privileged contexts. This type of vulnerability is particularly dangerous because it does not require user interaction beyond visiting a malicious webpage, making it suitable for drive-by attacks where no additional clicks are needed to trigger the exploit.
The operational impact of this vulnerability allows a remote attacker to perform unauthorized data exfiltration by reading sensitive information that was previously considered secure within the browser's sandboxed environment. This can lead to session hijacking if authentication tokens or cookies are exposed, allowing the attacker to impersonate legitimate users and gain access to their accounts on various web services. Furthermore, exposure of internal application state could facilitate further attacks against other components of the user system by revealing memory layouts or cryptographic keys used in secure communications. The severity is rated as medium because while it does not allow direct code execution or full system compromise, it significantly undermines the confidentiality guarantees provided by modern browsers and can serve as a stepping stone for more severe exploits that combine information leakage with buffer overflow vulnerabilities to achieve arbitrary code execution.
Mitigation strategies primarily involve upgrading Google Chrome to version 153.0.8010.52 or later, where these issues in the paint subsystem have been addressed through improved memory management and stricter isolation of rendering contexts. Organizations should enforce automated update policies to ensure all client machines are running patched versions promptly after release. Additionally, deploying browser security extensions that restrict canvas access or limit JavaScript execution on untrusted domains can provide an additional layer of defense against such exploitation attempts. Security teams should also monitor for indicators of compromise related to unusual memory usage patterns in the Chrome process and implement network-level controls to detect potential data exfiltration via encoded payloads hidden within image requests generated by compromised browsers. This incident underscores the importance of continuous patching cycles and rigorous code auditing focused on graphics subsystems, which are often complex and prone to subtle logic errors that can be leveraged for information disclosure attacks as defined in MITRE ATT&CK technique T1005, where data is collected from local system sources before being exfiltrated.