High severity · published Oct 27, 2026
CVE-2026-90442
Fireware OS Authenticated Stack Buffer Overflow in certd Allows Denial of Service
New
8.6
CVSS
–
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fireware OS · WatchGuard
2025.1 before 2026.4; 12.0 before 12.12.4; 12.0 before 12.5.22 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-90442
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-90442
psirt.watchguard.com
https://psirt.watchguard.com/CVE-2026-90442
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