Sigma rule: Potential JLI.dll Side-Loading

Rule

Title

Potential JLI.dll Side-Loading

Status

experimental

Level

high

Author

Swachchhanda Shrawan Poudel (Nextron Systems)

Date

2025-07-25

Modified

2025-10-06

File

rules/windows/image_load/image_load_side_load_jli.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potential DLL side-loading of jli.dll.
JLI.dll has been observed being side-loaded by Java processes by various threat actors, including APT41, XWorm,
and others in order to load malicious payloads in context of legitimate Java processes.

Log source

product

windows

category

image_load

Detection

selection:
    ImageLoaded|endswith: '\jli.dll'
filter_main_legitimate_install_paths:
    ImageLoaded|startswith:
        # Keeping the paths generic as jli.dll was found inside various directories of installed software
        - 'C:\Program Files\'
        - 'C:\Program Files (x86)\'
    Description: 'OpenJDK Platform binary'
    OriginalFileName: 'jli.dll'
    Product|startswith: 'OpenJDK Platform'
    Signed: 'true'
filter_optional_eclipse:
    ImageLoaded|startswith: 'C:\eclipse\plugins\'
condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*

False positives (as the rule lists them)

• Unknown

Tags

• attack.persistence
• attack.privilege-escalation
• attack.execution
• attack.stealth
• attack.t1574.001

MITRE ATT&CK ids this rule names

• T1574.001

References

• https://securelist.com/apt41-in-africa/116986/
• https://lab52.io/blog/snake-keylogger-in-geopolitical-affairs-abuse-of-trusted-java-utilities-in-cybercrime-operations/
• https://hijacklibs.net/entries/3rd_party/oracle/jli.html
• https://www.proofpoint.com/us/blog/threat-insight/phish-china-aligned-espionage-actors-ramp-up-taiwan-semiconductor-targeting

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/image_load/image_load_side_load_jli.yml