# CVE-2026-121638: WatchGuard AuthPoint Gateway Improper Certificate Validation Allows Man-in-the-Middle Attacks

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

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.

## Remediation

- fix: AuthPoint Authentication Gateway 7.6.0 (source: CNA: WatchGuard)

## Affected products and versions

- WatchGuard / AuthPoint Authentication Gateway: ≥ 1.0; < 7.6.0 (affected, semver). Source: CNA: WatchGuard

## Severity and prioritization

- CVSS 4.0: 9.1 (critical); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N; source: CNA: WatchGuard

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-295

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://psirt.watchguard.com/CVE-2026-121638 (CNA: WatchGuard; vendor-advisory)

## Provenance

- CNA: WatchGuard: https://www.cve.org/CVERecord?id=CVE-2026-121638; retrieved 2026-11-04; source updated 2026-11-04

Revision: a64af65417520ca3ad046151ca557198521de7a952dfc710e33a0650d6146ffd

Canonical: https://y2.dev/cve/CVE-2026-121638

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