Detection: Windows IIS Components Module Failed to Load

Updated Date: 2024-09-30 ID: 40c2ba5b-dd6a-496b-9e6e-c9524d0be167 Author: Michael Haag, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects when an IIS Module DLL fails to load due to a configuration problem, identified by EventCode 2282. This detection leverages Windows Application event logs to identify repeated failures in loading IIS modules. Such failures can indicate misconfigurations or potential tampering with IIS components. If confirmed malicious, this activity could lead to service disruptions or provide an attacker with opportunities to exploit vulnerabilities within the IIS environment. Immediate investigation is required to determine the legitimacy of the failing module and to mitigate any potential security risks.

Search

1`wineventlog_application` EventCode=2282 
2| stats  count min(_time) as firstTime max(_time) as lastTime by  EventCode dest Name ModuleDll 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `windows_iis_components_module_failed_to_load_filter`

Data Source

Name	Platform	Sourcetype	Source
Windows Event Log Application 2282	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Application'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_iis_components_module_failed_to_load_filter	`search *`

windows_iis_components_module_failed_to_load_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1505	Server Software Component	Persistence
T1505.004	IIS Components	Persistence

KillChainPhase.INSTALLATION

NistCategory.DE_AE

Cis18Value.CIS_10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	True

This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

IIS must be installed and Application event logs must be collected in order to utilize this analytic.

Known False Positives

False positives will be present until all module failures are resolved or reviewed.

Associated Analytic Story

IIS Components

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
A new IIS Module has been loaded and should be reviewed on $dest$.	25	50	50

The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Application`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Application`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 3