CVE-2026-79234 in Chrome
Summary
by MITRE • 08/26/2026
Injection in CSS in Google Chrome prior to 152.0.7977.65 allowed a remote attacker to potentially obtain sensitive information via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 08/26/2026
The vulnerability identified as an injection flaw within the Cascading Style Sheets engine of Google Chrome prior to version 152.0.7977.65 represents a significant risk to user privacy and data confidentiality. This issue stems from insufficient validation or sanitization mechanisms when processing CSS properties derived from untrusted sources, such as HTML content embedded in web pages. By crafting specific HTML structures that exploit the browser's style parsing logic, an attacker can manipulate how styles are applied to elements on a page. The core technical flaw lies in the ability of maliciously crafted input to bypass expected boundaries within the rendering engine, allowing for unintended side effects during the layout and paint phases of the browsing experience.
From a technical perspective, this vulnerability is classified under CWE-79, which covers Improper Neutralization of Input During Web Page Generation commonly known as Cross-Site Scripting or injection flaws. Although CSS itself does not execute code in the same manner as JavaScript, it can be leveraged for information disclosure through techniques such as style-based side-channel attacks. An attacker could potentially use crafted styles to detect specific properties of elements on a page that are otherwise inaccessible due to cross-origin restrictions. For instance, by observing how certain styles affect layout or visibility, an attacker might infer the presence of sensitive data like credit card numbers in autofill fields or other private user information stored within the browser's memory.
The operational impact of this vulnerability is primarily centered on confidentiality rather than integrity or availability. A remote attacker does not need physical access to the victim's machine but must trick a user into visiting a maliciously crafted web page. Once loaded, the exploit runs in the context of that site and can potentially exfiltrate sensitive information by leveraging CSS properties to probe for specific data patterns. The Chromium security team has rated this issue as Medium severity, indicating that while it is not immediately critical like remote code execution vulnerabilities, it poses a tangible threat to user privacy and could be used in targeted attacks against high-value targets where even partial data leakage can have severe consequences.
Mitigation strategies involve both immediate patching and long-term defensive coding practices. The primary remediation step for users is to update Google Chrome to version 152.0.7977.65 or later, which contains the necessary fixes to properly sanitize CSS inputs and prevent these injection vectors from succeeding. For developers integrating third-party content into their applications, it is crucial to implement strict Content Security Policy directives that restrict inline styles and ensure that any user-generated input undergoes rigorous sanitization before being rendered in a way that interacts with the browser's styling engine. Additionally, adopting defense-in-depth measures such as disabling JavaScript where not strictly necessary can reduce the attack surface for related exploits.
In terms of threat intelligence frameworks, this vulnerability aligns with ATT&CK technique T1059, specifically sub-techniques involving web browsers and potentially CSS-based side channels under data exfiltration methods. Understanding these mappings helps security teams prioritize patching efforts based on the potential for data theft rather than just system compromise. Organizations should monitor for indicators of exploitation related to unusual network traffic patterns originating from browser processes or unexpected DOM modifications that correlate with style injection attempts. Regular vulnerability assessments and penetration testing focused on web application input validation will further reduce the likelihood of such vulnerabilities being successfully exploited in production environments.