Potential SAP NetWeaver Webshell Creation

Status: experimental
Severity: medium
Log source: category file_event, product windows
Author: Elastic (idea), Swachchhanda Shrawan Poudel (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects the creation of suspicious files (jsp, java, class) in SAP NetWeaver directories, which may indicate exploitation attempts of vulnerabilities such as CVE-2025-31324.

Known false positives

Legitimate creation of jsc or java files in these locations

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1190` Exploit Public-Facing Application
Execution	`T1059.003` Command and Scripting Interpreter: Windows Command Shell

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 11: FileCreate

Rule body

title: Potential SAP NetWeaver Webshell Creation
id: 86a7c91f-98c3-4f14-a58d-d989421e1234
status: experimental
description: |
    Detects the creation of suspicious files (jsp, java, class) in SAP NetWeaver directories,
    which may indicate exploitation attempts of vulnerabilities such as CVE-2025-31324.
references:
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-31324
    - https://reliaquest.com/blog/threat-spotlight-reliaquest-uncovers-vulnerability-behind-sap-netweaver-compromise/
    - https://onapsis.com/blog/active-exploitation-of-sap-vulnerability-cve-2025-31324/
author: Elastic (idea), Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-04-28
tags:
    - attack.execution
    - attack.initial-access
    - attack.t1190
    - attack.persistence
    - attack.t1059.003
    - cve.2025-31324
    - detection.emerging-threats
logsource:
    product: windows
    category: file_event
detection:
    selection_path:
        TargetFilename|contains:
            - '\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\work'
            - '\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\root'
    selection_ext:
        TargetFilename|endswith:
            - '.jsp'
            - '.java'
            - '.class'
    condition: all of selection_*
falsepositives:
    - Legitimate creation of jsc or java files in these locations
level: medium

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_path`

selection_path:
    TargetFilename|contains:
        - '\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\work'
        - '\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\root'

Stage 2: `selection_ext`

selection_ext:
    TargetFilename|endswith:
        - '.jsp'
        - '.java'
        - '.class'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`TargetFilename`	ends_with	`.class` corpus 2 (sigma 2) `.java` corpus 2 (sigma 2) `.jsp` corpus 5 (sigma 4, splunk 1)	`field:"TargetFilename" kind:ends_with`
`TargetFilename`	match	`\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\root` `\j2ee\cluster\apps\sap.com\irj\servlet_jsp\irj\work`	`field:"TargetFilename" kind:match`