Vulnerability · Published Oct 27, 2026 · Assigned by WatchGuard

CVE-2026-93864Fireware OS Link Following in firewalld Allows Local Arbitrary File Overwrite as Root

High 7.1

In plain English

A high-severity path traversal in Fireware OS from WatchGuard. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities).

Severity (CVSS 4.0)7.1High

Exploit odds (30 days)0.1%top 97.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A link following vulnerability in WatchGuard Fireware OS’s firewall daemon allows a local attacker with code execution as a low-privileged system process to overwrite arbitrary files with root privileges, and to tamper with firewall IP set data, by planting a crafted file system object and triggering a list update. Written content is partially constrained.

Affected products (as reported)

Vendor	Product	Versions
WatchGuard	Fireware OS	2025.1 – before 2026.412.0 – before 12.12.4
WatchGuard	Fireware OS	12.0 – before 12.5.22

Weakness: CWE-22, CWE-377, CWE-59, CWE-73 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H

References

https://psirt.watchguard.com/CVE-2026-93864 vendor-advisory