CVE-2026-93864 PUBLISHED

Fireware OS Link Following in firewalld Allows Local Arbitrary File Overwrite as Root

Assigner: WatchGuard
Reserved: 18.09.2026 Published: 27.10.2026 Updated: 27.10.2026

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.

Metrics

CVSS 4.0

CVSS 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
CVSS Score: 7.1

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Local	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	High
Attack Requirements	Present	Availability	High	Availability	High
Privileges Required	Low
User Interaction	None

CVSS 4.0

Product Status

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 2025.1 to 2026.4 (excl.) affected from 12.0 to 12.12.4 (excl.)

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 12.0 to 12.5.22 (excl.)

Exploits

WatchGuard is not aware of any exploitation of this vulnerability in the wild.

Solutions

Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22

Credits

WatchGuard AI Security Research finder

References

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

Problem Types

CWE-22 CWE
CWE-377 CWE
CWE-59 CWE
CWE-73 CWE