CVE-2026-103630

chromium-browser: Use after free in FedCM

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Published Oct 2, 2026 CVSS 3.1 · 9.6 Critical EPSS < 1% KEV · Not listed
Description
Use after free in FedCM in Google Chrome prior to 154.0.8037.97 allowed a remote attacker to execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)

Analysis

AI-generated

Technical impact

A use‑after‑free flaw in the FedCM implementation of Google Chrome allows a remote attacker to execute arbitrary code outside the browser sandbox through a crafted HTML page. The vulnerability, rated high by Chromium, could compromise confidentiality, integrity, and availability of the affected system if an unprivileged web page triggers the exploit.

Affected Systems

Google Chrome users who have not upgraded to version 154.0.8037.97 or later are affected. The flaw exists in all prior releases of Chrome and can impact any user visiting a site that can deliver a malicious HTML payload to the browser.

Risk and Exploitability

The vulnerability carries a high severity rating with a CVSS score of 9.6. The EPSS score is < 1%, and the vulnerability is not listed in CISA’s KEV catalog. However, the potential for remote code execution outside the sandbox underscores a significant risk if an attacker can deliver a crafted page to the user. The likely attack vector is a remotely hosted malicious website that triggers the use‑after‑free condition during FedCM processing.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Update Google Chrome to version 154.0.8037.97 or later.
  • If an upgrade cannot be performed immediately, disable the FedCM feature by launching Chrome with the flag --disable-features=FedCM or by setting the corresponding experimental flag to off through chrome://flags.
  • Avoid visiting untrusted websites that could supply malicious HTML and use a strict content‑security policy to limit script execution if possible.

Generated by OpenCVE AI on October 7, 2026 at 07:54 UTC.

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4833-1 chromium security update
Debian DSA Debian DSA DSA-6553-1 chromium security update
History
Type Values Removed Values Added
Title chromium-browser: Use after free in FedCM
References
Metrics threat_severity

None

 threat_severity

Important
Type Values Removed Values Added
Title Use after Free in FedCM Enables Remote Code Execution in Google Chrome
Type Values Removed Values Added
CPEs cpe:2.3:a:google:chrome:*:*:*:*:*:*:*:*
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}
Type Values Removed Values Added
First Time appeared Google
Google chrome
Vendors & Products Google
Google chrome
Type Values Removed Values Added
Title Use after Free in FedCM Enables Remote Code Execution in Google Chrome
Type Values Removed Values Added
Description Use after free in FedCM in Google Chrome prior to 154.0.8037.97 allowed a remote attacker to execute arbitrary code outside the sandbox via a crafted HTML page. (Chromium security severity: High)
Weaknesses CWE-416
References
Earlier changes (2)
Weaknesses

Sources

Status
PUBLISHED
Assigner
Chrome
Published
Updated
Oct 6, 2026, 1:09 PM
Reserved
Sep 30, 2026, 11:12 PM

View source JSON

Updated
Oct 6, 2026, 1:09 PM

JSON

Status
Analyzed
Published
Oct 2, 2026, 4:16 PM
Modified
Oct 6, 2026, 4:22 PM

View source JSON

Severity
Important
Public date
Oct 2, 2026, 4:07 PM

View source Bugzilla JSON

Updated
Oct 7, 2026, 8:00 AM

JSON