CVE-2026-86134: high-severity vulnerability in WatchGuard Fireware OS
Fireware OS Pre-Authentication NULL Pointer Dereference Allows Remote Denial of Service
Published
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.4%
exploitation probability
0.4%top 70% of all CVEs
observed exploitation
nono source reports it
A NULL pointer dereference vulnerability in the WatchGuard Fireware OS authentication process allows a remote, unauthenticated attacker to crash the management daemon by sending a specially request to the login interface, resulting in a denial of service.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
WatchGuard · Fireware OSRelated CVEs — WatchGuard Fireware OS
In the same product, most dangerous first.
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