CVE-2026-116606: in the CISA KEV catalogue
Barracuda Networks Email Security Gateway (ESG) Authentication Bypass Using an Alternate Path or Channel Vulnerability. CISA added CVE-2026-116606 to the Known Exploited Vulnerabilities catalogue on 2026-11-10 with a default due date of 2026-11-13. Known ransomware campaign use: Unknown. Forensic triage flag: Yes.
Barracuda Networks Email Security Gateway (ESG) contains an authentication bypass using an alternate path or channel that could allow an unauthenticated remote attacker to invoke a configuration-import function and restore a crafted, compatible backup archive, resulting in unauthorized modification of the appliance’s global configuration. This vulnerability can be chained with CVE-2026-111560. (CISA description)
- Vendor / product
- Barracuda Networks Barracuda Email Security Gateway (ESG)
- CWE
- CWE-288
- CISA 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.
- EPSS
- 1.6%, percentile 76 (scored 2026-11-10)
EPSS puts about 1.6 in 100 odds (1.6%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 76% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
- https://trust.barracuda.com/security/pre-authentication-authorization-bypass-command-injection
- https://github.com/mandiant/Vulnerability-Disclosures/blob/master/2026/MNDT-2026-0042.md
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-116606
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2026-116606 in the CISA KEV catalogue?
Yes. CISA added CVE-2026-116606 (Barracuda Networks Email Security Gateway (ESG) Authentication Bypass Using an Alternate Path or Channel Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2026-11-10. CISA's default due date for it is 2026-11-13.
Is CVE-2026-116606 used in ransomware attacks?
CISA marks known ransomware campaign use as Unknown for CVE-2026-116606. That means CISA lacks confirmation, not that ransomware groups do not use it.
What should I do about CVE-2026-116606?
CISA's 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.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2026-116606