CVE-2026-17806 in Chrome
Summary
by MITRE • 07/30/2026
Insufficient validation of untrusted input in Extensions in Google Chrome prior to 151.0.7922.72 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Medium)
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Analysis
by VulDB Data Team • 07/30/2026
This vulnerability represents a critical sandbox escape risk in google chrome's extension architecture that emerged from insufficient input validation mechanisms within the browser's rendering pipeline. The flaw existed in versions prior to 151.0.7922.72 and specifically targeted the extension system's handling of untrusted data from web pages, creating a pathway for attackers who had already compromised a renderer process to break out of chrome's security boundaries. The vulnerability stems from inadequate sanitization of user-supplied content that flows through the extension API, allowing malicious html payloads to manipulate extension behavior in ways that bypass chrome's intended security model.
The technical exploitation of this vulnerability leverages the fact that chrome extensions operate with elevated privileges while maintaining a sandboxed environment that should prevent them from accessing system resources or other processes. When untrusted input reaches the extension subsystem without proper validation, an attacker can craft html content that triggers specific code paths within extension handlers, potentially manipulating extension permissions or accessing restricted APIs. This represents a classic case of insufficient input validation where the system fails to properly sanitize data before processing it through privileged execution contexts. The chromium security severity rating of medium reflects the complexity required to achieve exploitation, which necessitates prior compromise of the renderer process, but the potential impact remains severe due to the sandbox escape capability.
The operational impact of this vulnerability extends beyond simple privilege escalation as it fundamentally undermines chrome's security architecture and could enable attackers to gain persistent access to user systems. Once an attacker achieves a sandbox escape through this vector, they can potentially access other browser processes, steal sensitive data, or establish backdoors that persist across browsing sessions. The vulnerability affects the broader chrome extension ecosystem and could be exploited across multiple extensions that rely on user-provided content without proper sanitization. This creates a cascading risk where a single compromised extension could serve as a gateway for broader system compromise.
Mitigation strategies should focus on immediate version updates to chrome 151.0.7922.72 or later, which contain the necessary patches addressing the input validation gaps in extension processing. Organizations should also implement additional monitoring for unusual extension behavior and consider restricting extension permissions where possible. The vulnerability aligns with attack patterns described in the attack tree framework under privilege escalation techniques, specifically targeting sandbox escape vectors that are commonly exploited in advanced persistent threat campaigns. Security teams should also review their incident response procedures to account for potential sandbox escape scenarios and ensure appropriate network monitoring can detect anomalous extension behavior that might indicate exploitation attempts.