CVE-2026-86128: high-severity vulnerability in WatchGuard Fireware OS
Fireware OS NULL Pointer Dereference in NetFlow IPv6 Traffic Processing Allows Remote Denial of Service
Published · Updated
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.4%
exploitation probability
0.4%top 72% of all CVEs
observed exploitation
nono source reports it
A NULL pointer dereference vulnerability in Fireware OS's NetFlow packet-processing feature allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted IPv6 packet.
CVSS:4.0/AV:N/AC:L/AT:P/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
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