8.6
HighCVSS 4.0 · from WatchGuard
CVE-2026-90442
Fireware OS Authenticated Stack Buffer Overflow in certd Allows Denial of Service
Fireware OS · Stack buffer overflow · CWE-121AffectedFireware OS, Fireware OS
FixUpdate to 2026.4, 12.12.4, 12.5.22 or newer
PublishedOct 27, 15:52 · WatchGuard
ScoredOct 27 · 8.6 · WatchGuard
Exploit code publicNone known · checked 21:18 UTC
ExploitedNone known · CISA KEV checked 22:07 UTC
What we know
No known exploitation. CISA KEV, checked 22:07 UTC.
No public exploit code known. Exploit-DB, Metasploit, Nuclei, checked 21:18 UTC.
An attacker needs network access and an account. CVSS: network, high privileges.
A successful attack can read and change data and take the service down. CVSS: high impact on confidentiality, integrity and availability.
Description
A stack-based buffer overflow vulnerability in the Fireware OS certd process allows an authenticated attacker with access to the Firebox management interface to crash the certificate management service and potentially execute arbitrary code by sending a specially crafted request.
From WatchGuard
Affected and fixed versions
ProductAffectedFixed inFireware OS2025.1 – before 2026.42026.4Fireware OS12.0 – before 12.12.412.12.4Fireware OS12.0 – before 12.5.2212.5.22
Exploit code
Exploit-DBnone knownMetasploitnone knownNucleinone known