CVE-2026-121204: Incomplete cleanup in DevTools in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to bypass web
CVE-2026-121204 is a high-severity flaw (CVSS 8.8) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Incomplete cleanup in DevTools in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: Low)
Why this priority
- High severity
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 8.8 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 0.2% (top 88%) |
| CISA exploited list | No |
| Weakness | CWE-459 |
| Published | 2026-11-03 |
| Last modified | 2026-11-04 |
Last updated 2026-11-04 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Research and news
- VulDB Recent Entries: CVE-2026-121204 | Google Chrome up to 156.0.8078.79 DevTools access control 2026-11-03
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-121204?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-121204 being exploited?
CVE-2026-121204 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-121204 affect?
CVE-2026-121204 affects affected software. Severity is high (CVSS 8.8). Incomplete cleanup in DevTools in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: Low)
How urgent is CVE-2026-121204?
Priority 34/100. High severity
Software pages
Google Chrome vulnerabilities · Chromium vulnerabilities