Is there a public exploit for CVE-2026-121638?

No public exploit for CVE-2026-121638 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-2026-121638?

CVE-2026-121638 scores CVSS 9.1 (v4.0), rated critical.

What does CVE-2026-121638 affect?

CVE-2026-121638 affects WatchGuard AuthPoint Authentication Gateway.

9.1 Critical

An Improper Certificate Validation vulnerability in WatchGuard AuthPoint Gateway allows an attacker with an on-path network position to…

CVE-2026-121638

An Improper Certificate Validation vulnerability in WatchGuard AuthPoint Gateway allows an attacker with an on-path network position to intercept and modify communications between the AuthPoint Gateway and local authentication providers.

Assessment

CVSS: 9.1 (v4.0)
Severity: Critical
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 November 2026
Last updated: 4 November 2026
Affected: WatchGuard · AuthPoint Authentication Gateway
Assigner: WatchGuard

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

https://psirt.watchguard.com/CVE-2026-121638

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