CVE-2026-116606Barracuda Email Security Gateway (ESG) Authentication Bypass
Authentication Bypass Allows Global Configuration Restore in Barracuda Email Security Gateway
Published Nov 2, 2026 · Updated Nov 3, 2026 · Also known as EUVD-2026-115149, GHSA-9fcr-mp7p-hprv
Key Facts
Patch immediately- CVE-2026-116606 is a critical-severity vulnerability (CVSS 9.3 v4) affecting Barracuda Email Security Gateway (ESG).
- It is exploited in the wild, listed in Industry KEV feed since Nov 9, 2026. No public exploit code is known.
- EPSS estimates a 1.6% probability of exploitation in the next 30 days.
- Fixed versions are available, including Barracuda Email Security Gateway (ESG) 9.4.0.030.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Scores
CVSS v4
9.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS (30-day exploit likelihood)
1.6%
Higher than 75.9% of all scored CVEs
Exploit maturity
Exploited (KEV)
ATLAS score
59/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Nov 9, 2026
7 days after publication
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Exploited (KEV)
Public exploit code
1
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
Description
An authentication bypass in Barracuda Email Security Gateway versions earlier than 9.4.0.030 allows 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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Nov 9, 2026 | n/a | Not reported |
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Barracuda Email Security Gateway (ESG) | See advisory | 9.4.0.030 |
Patched Releases
Barracuda Email Security Gateway (ESG)
9.4.0.030
Timeline
Publicly disclosed
Nov 2, 2026
Last updated
Nov 3, 2026
Added to Industry KEV feed
Nov 9, 2026
Weakness Type
- CWE-288 Authentication Bypass Using an Alternate Path or Channel
References
FAQ
Common Questions.
An authentication bypass in Barracuda Email Security Gateway versions earlier than 9.4.0.030 allows 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.
Affected: Barracuda Email Security Gateway (ESG). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Nov 9, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Barracuda Email Security Gateway (ESG) 9.4.0.030.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2026-116606 On Your Attack Surface?
Brandefense matches it against the products discovered on your perimeter and opens a finding the day a CVE like this is listed.
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