Barracuda Networks Email Security Gateway (ESG) Authentication Bypass Using an Alternate Path or Channel Vulnerability
Affected vendor/product: Barracuda Networks Barracuda Email Security Gateway (ESG)
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA KEV date added: 2026-11-10
Due date: 2026-11-13
Known ransomware campaign use: Unknown