CVE-2026-4315

What this means for your business

• It affects Watchguard Fireware. It matters if your company, or a supplier that handles your data, runs it.
• An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
• FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 6% of all known flaws.

What to do

1. 1Check whether your company or your suppliers run Watchguard Fireware, and which version. The affected versions are listed further down this page.
2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.