Is CVE-2026-93864 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-93864 being exploited in the wild.

How severe is CVE-2026-93864?

Informational severity, published 27 October 2026.

Which products and versions are affected?

Watchguard Fireware OS Default: 2025.1 through 2026.3, 12.0 through 12.12.3; T15/T35: 12.0 through 12.5.21.

Is there a fix for CVE-2026-93864?

Yes: fixed in Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-93864 attacked?

It is attacked with local access, in a network appliance.

Am I affected by CVE-2026-93864?

Check whether you run Watchguard Fireware OS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-93864: WatchGuard Fireware OS arbitrary file overwrite via link following

CVE-2026-93864 · Severity: info · Published 2026-10-27

WatchGuard Fireware OS is network firewall software that protects organizations by controlling and monitoring traffic. A vulnerability in the firewall daemon allows a local attacker who has already compromised a low-privileged system process to escalate privileges and overwrite critical files with root-level access, potentially disabling security controls or modifying firewall policies.

Technologies: Watchguard Fireware OS. Vendors: Watchguard.

Quick answers

Is CVE-2026-93864 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-93864 being exploited in the wild.
How severe is CVE-2026-93864?: Informational severity, published 27 October 2026.
Which products and versions are affected?: Watchguard Fireware OS Default: 2025.1 through 2026.3, 12.0 through 12.12.3; T15/T35: 12.0 through 12.5.21.
Is there a fix for CVE-2026-93864?: Yes: fixed in Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-93864 attacked?: It is attacked with local access, in a network appliance.
Am I affected by CVE-2026-93864?: Check whether you run Watchguard Fireware OS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22

Technical details

A link following vulnerability (CWE-59) in the firewall daemon's file handling allows a local attacker with code execution as a low-privileged system process to plant a crafted symlink and trigger a file update operation, causing the daemon to overwrite arbitrary files with root privileges. The attacker can exploit this to tamper with firewall IP set data or other system files; written content is partially constrained.

Affected products

WatchGuard Fireware OS Default: 2025.1 through 2026.3, 12.0 through 12.12.3; T15/T35: 12.0 through 12.5.21

Timeline

2026-10-27: disclosed

References

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

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