CVE-2026-9926: Heap buffer overflow in ANGLE in Google Chrome prior to 148

Synopsis

Heap buffer overflow in the ANGLE graphics layer of Google Chrome prior to version 148.0.7778.216 allows a remote attacker who has already compromised the Chrome renderer process to escape the browser sandbox via a crafted HTML page. The vulnerability is reachable over the network but requires the victim to visit a malicious page, and exploitation is made harder by the high attack complexity rating (AC:H) in the CVSS vector. Successful exploitation gives the attacker full read, write, and crash capability outside the sandbox, effectively breaking Chrome's primary isolation boundary. A patched-image rebuild at 148.0.7778.216 is available on HarborGuard for environments running an affected version.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The attacker must reach the victim over the network by serving a crafted HTML page from a remote origin.

• AuthenticationNot required

  No account or credential is needed; any unauthenticated remote attacker can attempt to deliver the exploit page.

• Victim interactionRequired

  The victim must navigate to or be social-engineered into loading the attacker-controlled HTML page in the affected Chrome browser.

• Attack complexityDetail

  Exploitation is rated AC:H, meaning the attacker must first have compromised the renderer process before the heap overflow can be leveraged for sandbox escape, introducing a significant pre-condition.

Blast Radius

• A successful attacker reads data from outside the Chrome sandbox, including files and memory regions that the renderer would normally be blocked from accessing.
• The attacker writes arbitrary data outside the sandbox boundary, enabling persistent changes to the host filesystem or injection into other processes.
• The attacker can crash the host-side Chrome process or dependent system components, causing a denial of service at the browser or OS level.
• Because the sandbox is fully escaped, any subsequent payload runs with the privileges of the user who launched Chrome, not the restricted renderer context.