IIS HTTP Logging Disabled via dontLog Configuration Change (Windows)
Alerts on IIS configuration updates that disable HTTP logging by setting dontLog to true for successful requests.
- Product
- windows
- Service
- iis-configuration
- Author
- frack113 (SigmaHQ), DRL 1.1
- Published
- 2024-10-06
- Updated
- 2026-07-31
ATT&CK techniques
PersistenceRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags an IIS configuration change that sets /system.webServer/httpLogging/@dontLog to true, which disables logging for successful HTTP requests. Attackers may impair detection by reducing web activity visibility after gaining access. The detection relies on IIS configuration change telemetry that records EventID 29 along with the specific configuration path and new value.
Reporting behind it
- learn.microsoft.comhttps://learn.microsoft.com/en-us/iis/manage/provisioning-and-managing-iis/configure-logging-in-iis
- microsoft.comhttps://www.microsoft.com/en-us/security/blog/2022/12/12/iis-modules-the-evolution-of-web-shells-and-how-to-detect-them/
- learn.microsoft.comhttps://learn.microsoft.com/en-us/iis/configuration/system.webserver/httplogging
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/iis-configuration/win_iis_logging_http_disabled.yml
Changelog
v2- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: IIS HTTP Logging Disabled via dontLog Configuration Change (Windows)
id: 973b10f3-c5d6-4280-b795-c7053871e711
status: test
description: This rule flags an IIS configuration change that sets /system.webServer/httpLogging/@dontLog to true, which disables logging for successful HTTP requests. Attackers may impair detection by reducing web activity visibility after gaining access. The detection relies on IIS configuration change telemetry that records EventID 29 along with the specific configuration path and new value.
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://learn.microsoft.com/en-us/iis/configuration/system.webserver/httplogging
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/iis-configuration/win_iis_logging_http_disabled.yml
author: frack113, Huntrule Team
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: /system.webServer/httpLogging/@dontLog
NewValue: "true"
condition: selection
falsepositives:
- Unknown
level: high
license: DRL-1.1
related:
- id: e8ebd53a-30c2-45bd-81bb-74befba07bdb
type: derived