An Insecure Deserialization vulnerability in WatchGuard Fireware OS allows an attacker that has obtained write access to the local filesystem through another vulnerabi…

Code

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No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Mar 30, 2026 · NIST NVD

   Detected

   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.

2. Aug 28, 2026 · NIST NVD

   Updated

   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.

Affected

• cpe watchguard/firewareversion unspecified

Sources

• CVE.orgVulnerability recordCVE-2026-4266

  Official CVE identifier

  cve.org
• NIST NVDVulnerability recordCVE-2026-4266

  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 Fire

  nvd.nist.gov

References

• Broken Link · psirt.watchguard.com
• Vendor Advisory · watchguard.com