High severity · published Sep 29, 2026
CVE-2026-81433
Fireware OS Pre-Authentication Stack Buffer Overflow in fingerd Allows Remote Code Execution
8.7
CVSS
0.2%
EPSS
No
On KEV
Description
A stack-based buffer overflow vulnerability in WatchGuard Fireware OS's DHCP fingerprinting daemon (fingerd) allows an unauthenticated attacker with adjacent network access to execute arbitrary code or crash the process by sending a specially crafted DHCP packet.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fireware OS · WatchGuard
2026.3 before 2026.3.2; 2025.0 before 2026.2.3; 12.0 before 12.12.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81433
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-81433
vendor-advisory
https://psirt.watchguard.com/CVE-2026-81433
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