CVE-2026-11242: Insufficient validation of untrusted input in Plugins in Google Chrome prior to 149

Synopsis

This is an insufficient input validation vulnerability in the Plugins component of Google Chrome prior to version 149.0.7827.53. The flaw is reachable over the network with no authentication required, but exploitation assumes the attacker has already compromised the Chrome renderer process. Successful exploitation leaks cross-origin data, meaning an attacker can read content from web origins other than their own, violating the browser's same-origin boundary. A patched-image rebuild at 149.0.7827.53 is available on HarborGuard for affected environments.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must be able to reach the target over the network and deliver a crafted HTML page to the victim's browser.

• AuthenticationNot required

  No authentication or account credentials are required to deliver the malicious page.

• Victim interactionNot required

  No user interaction is required beyond the renderer process already being compromised; no additional click or social-engineering step is needed at exploitation time.

• Attack complexityDetail

  Attack complexity is low, meaning the exploit is reliable and does not depend on race conditions or specific memory layout, though it does presuppose a pre-existing renderer compromise.

Blast Radius

• Reads cross-origin data that the same-origin policy would normally block, such as response bodies from other sites loaded in the same browser session.
• Leaks potentially sensitive content from authenticated sessions on third-party origins, for example intranet pages or logged-in web application responses.
• Confidentiality impact is high with no integrity or availability impact, so the attacker gains information but cannot modify or destroy data through this vulnerability alone.