CVE-2026-79186 in Chrome
Summary
by MITRE • 08/26/2026
Incorrect authorization in Network in Google Chrome prior to 152.0.7977.65 allowed a remote attacker who had compromised the renderer process to bypass site isolation 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 incorrect authorization issue within the Google Chrome browser prior to version 152.0.7977.65 represents a critical failure in the enforcement of process-level access controls, specifically targeting the site isolation mechanism. Site isolation is a fundamental security architecture employed by modern web browsers to prevent cross-site scripting and data theft attacks by ensuring that each website runs in its own distinct renderer process with isolated memory space. This architectural decision effectively mitigates side-channel attacks such as Spectre or Meltdown variants that could otherwise allow an attacker reading from one site's memory to infer sensitive information about another active tab, such as banking credentials or private emails. The flaw described indicates a lapse in the authorization logic governing how renderer processes interact with network resources and other browser components, allowing a compromised renderer process to exceed its intended permissions.
From a technical perspective, this vulnerability falls under the category of improper access control vulnerabilities, commonly referenced by the Common Weakness Enumeration (CWE) as CWE-269: Improper Privilege Management or more specifically within web contexts as CWE-862: Missing Authorization. The core issue lies in the browser's internal security model failing to validate whether a renderer process originating from one origin has legitimate authority to access resources, cookies, or network states associated with another origin. When an attacker crafts a malicious HTML page designed to exploit this flaw, they can leverage their foothold within a compromised renderer process to bypass these isolation boundaries. This effectively collapses the security perimeter that Chrome maintains between different websites, allowing data leakage across origins where it should be strictly prohibited.
The operational impact of this vulnerability is significant for users who rely on site isolation as their primary defense against cross-site attacks. If an attacker successfully exploits this flaw through a crafted HTML page hosted on a malicious website or delivered via phishing, they can potentially access sensitive user data from other open tabs without triggering standard security alerts. This could lead to unauthorized access to personal information, session hijacking, or the ability to perform actions on behalf of the user in other web applications. The Chromium project has classified this issue with a medium severity rating, reflecting its potential for exploitation by remote attackers who have already achieved code execution within a renderer process, which is often achievable through complex multi-stage attack chains involving zero-day exploits in browser plugins or rendering engines.
To mitigate the risks associated with this vulnerability, users are strongly advised to update their Google Chrome installation immediately to version 152.0.7977.65 or later, where these authorization checks have been corrected and reinforced. For organizations deploying Chrome at scale, it is imperative to ensure that automatic updates are enabled so that endpoints receive security patches promptly upon release. Additionally, administrators should consider implementing strict content security policies and restricting the execution of untrusted scripts in browser environments where possible. Monitoring for unusual network activity originating from renderer processes may also provide early indicators of exploitation attempts, although the primary defense remains timely patching to close the authorization gap identified by Chromium engineers.