Previously Installed IIS Module Was Removed

testlow
log source: windows · iis-configurationauthor Nasreddine Bencherchalidate 2024-10-06
01

description

What this is, in brief.

Detects the removal of a previously installed IIS module.

02

tags

attack.persistenceattack.defense-impairmentattack.t1685.001attack.t1505.004
03

rule source (YAML)

title: Previously Installed IIS Module Was Removed
id: 9e1a1fdf-ee58-40ce-8e15-b66ca5a80e1f
status: test
description: Detects the removal of a previously installed IIS module.
references:
    - https://learn.microsoft.com/en-us/iis/manage/provisioning-and-managing-iis/configure-logging-in-iis
    - https://www.microsoft.com/en-us/security/blog/2022/12/12/iis-modules-the-evolution-of-web-shells-and-how-to-detect-them/
    - https://www.microsoft.com/en-us/security/blog/2022/07/26/malicious-iis-extensions-quietly-open-persistent-backdoors-into-servers/
    - https://learn.microsoft.com/en-us/iis/get-started/introduction-to-iis/iis-modules-overview
author: Nasreddine Bencherchali
date: 2024-10-06
tags:
    - attack.persistence
    - attack.defense-impairment
    - attack.t1685.001
    - attack.t1505.004
logsource:
    product: windows
    service: iis-configuration
detection:
    selection:
        EventID: 29
        Configuration|contains: '/system.webServer/modules/remove'
    condition: selection
falsepositives:
    - Legitimate administrator activity
# Note: Upgrade after an initial baseline
level: low
04

detects techniques (2)

ATT&CK techniques this enables or maps to.

05

references

External citations — patches, advisories, analysis.