Skip to content
Nuclei Templates

EXPN Mail Server Detect

ID: expn-mail-detect

Severity: info

Author: r3dg33k,userdehghani

Tags: mail,expn,network,detect,smtp,detection,tcp

Description

Section titled “Description”

The “EXPN” can be used by attackers to learn about valid usernames on the target system. On some SMTP servers, EXPN can be used to show the subscribers of a mailing list subscription lists are generally considered to be sensitive information.

YAML Source

Section titled “YAML Source”
id: expn-mail-detect


info:
  name: EXPN Mail Server Detect
  author: r3dg33k,userdehghani
  severity: info
  description: |
    The "EXPN" can be used by attackers to learn about valid usernames on the target system. On some SMTP servers, EXPN can be used to show the subscribers of a mailing list subscription lists are generally considered to be sensitive information.
  metadata:
    max-request: 1
  tags: mail,expn,network,detect,smtp,detection,tcp


tcp:
  - inputs:
      - data: "65686c6f20636865636b746c730a"
        type: hex
    read-size: 2048


    host:
      - "{{Hostname}}"
    port: 25,2525,465,587


    matchers:
      - type: word
        words:
          - "250-EXPN"
# digest: 4b0a00483046022100f8e5cd3a121bcabec20a27e0138f1889cf6a3414b88ff22804573c7541b7efea022100b31924d7889f073f554fccdb8fbac0857bcdbc356aa2035893f5459f3d66ff42:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

Section titled “Guide to check the vulnerabilities”

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

Terminal window
$ nuclei -u "URL" -t "network/detection/expn-mail-detect.yaml"

View on Github