CVE-2026-4266
6.7 · MEDIUMOverview
CVE-2026-4266 is a medium-severity vulnerability affecting watchguard fireware. It was published on March 30, 2026 and has a CVSS 3.1 base score of 6.7 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.7, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
An Insecure Deserialization vulnerability in WatchGuard Fireware OS allows an attacker that has obtained write access to the local filesystem through another vulnerability to execute arbitrary code in the context of the portald user.
Note, this vulnerability does not affect Firebox platforms that do not support the Access Portal feature, including the T15 and T35.
Remediation
Check the references section for vendor advisories and patches from watchguard. Update fireware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| watchguard | fireware | >= 2025.1, < 2026.2 | Affected |
Frequently Asked Questions
What is CVE-2026-4266?
CVE-2026-4266 is a medium-severity vulnerability affecting watchguard fireware. It was published on March 30, 2026 and has a CVSS 3.1 base score of 6.7 (MEDIUM).
How severe is CVE-2026-4266?
This vulnerability has a CVSS 3.1 base score of 6.7, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-4266?
Check the references section for vendor advisories and patches from watchguard. Update fireware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-4266?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-4266 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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