Successful IIS Shortname Fuzzing Scan — Sigma Rule

Rule metadata and linked tags

Author: frack113. Source status: test; severity: medium. Source dates: 2021-10-06 / 2023-01-02.

{
  "category": "webserver"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: f89c3b95454e26a8896374efe6c2258fc7fe396b08784a03ce6c8e7a13c893e5

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Successful IIS Shortname Fuzzing Scan
id: 7cb02516-6d95-4ffc-8eee-162075e111ac
status: test
description: When IIS uses an old .Net Framework it's possible to enumerate folders with the symbol "~"
references:
    - https://github.com/projectdiscovery/nuclei-templates/blob/9d2889356eebba661c8407038e430759dfd4ec31/fuzzing/iis-shortname.yaml
    - https://www.exploit-db.com/exploits/19525
    - https://github.com/lijiejie/IIS_shortname_Scanner
author: frack113
date: 2021-10-06
modified: 2023-01-02
tags:
    - attack.initial-access
    - attack.t1190
logsource:
    category: webserver
detection:
    selection:
        cs-uri-query|contains: '~1'
        cs-uri-query|endswith: 'a.aspx'
        cs-method:
            - GET
            - OPTIONS
        # Success only
        sc-status:
            - 200
            - 301
    condition: selection
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/projectdiscovery/nuclei-templates/blob/9d2889356eebba661c8407038e430759dfd4ec31/fuzzing/iis-shortname.yaml
• https://www.exploit-db.com/exploits/19525
• https://github.com/lijiejie/IIS_shortname_Scanner