Is there a public exploit for CVE-2026-121039?

No public exploit for CVE-2026-121039 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121039?

CVE-2026-121039 scores CVSS 5.3 (v3.1), rated medium.

What does CVE-2026-121039 affect?

CVE-2026-121039 affects Google Chrome.

5.3 Medium

Incorrect authorization in Proxy Auth in Google Chrome prior to 157.0.8103.38 allowed an adjacent attacker to obtain sensitive information…

CVE-2026-121039

Incorrect authorization in Proxy Auth in Google Chrome prior to 157.0.8103.38 allowed an adjacent attacker to obtain sensitive information via crafted network traffic. (Chromium security severity: Medium)

Assessment

CVSS: 5.3 (v3.1)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 4 November 2026
Affected: Google · Chrome
Assigner: Chrome

CVSS vectorCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

At the source

EUVD (ENISA)

References

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