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Anonymous connection


Due to an improper configuration of the server (e.g., an FTP service with username: anonymous and password: guest or an SMTP open relay), it is possible to make anonymous connections to it and access otherwise protected resources.


Read and/or modify files within the service.


Configure the services to avoid services enumeration or to connect to these anonymously.


Anonymous attacker from adjacent network.

Expected Remediation Time

⌚ 30 minutes.


Default score using CVSS 3.1. It may change depending on the context of the vulnerability.


  • Attack vector: A
  • Attack complexity: L
  • Privileges required: N
  • User interaction: N
  • Scope: U
  • Confidentiality: L
  • Integrity: L
  • Availability: N


  • Exploit code madurity: X
  • Remediation level: O
  • Report confidence: X


  • Vector string: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:X/RL:O/RC:X
  • Score:
    • Base: 5.4
    • Temporal: 5.2
  • Severity:
    • Base: Medium
    • Temporal: Medium

Code Examples

Compliant code

Correctly configure services to deny anonymous authentication

"$schema": "",
"iisSettings": {
"windowsAuthentication": false,
"anonymousAuthentication": false,

Non compliant code

A service is configured to allow anonymous authentication

"$schema": "",
"iisSettings": {
"windowsAuthentication": false,
"anonymousAuthentication": true,


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