Sigma rule: Potential Pikabot Hollowing Activity

Rule

Title

Potential Pikabot Hollowing Activity

Status

test

Level

high

Author

Andreas Braathen (mnemonic.io)

Date

2023-10-27

Modified

2024-01-26

File

rules-emerging-threats/2023/Malware/Pikabot/proc_creation_win_malware_pikabot_rundll32_hollowing.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the execution of rundll32 that leads to the invocation of legitimate Windows binaries.
The malware Pikabot has been seen to use this technique for process hollowing through hard-coded Windows binaries

Log source

product

windows

category

process_creation

Detection

selection:
    ParentImage|endswith: '\rundll32.exe'
    Image|endswith:
        # Note: Only add processes seen used by Pikabot to avoid collision with other strains of malware
        - '\SearchFilterHost.exe'
        - '\SearchProtocolHost.exe'
        - '\sndvol.exe'
        - '\wermgr.exe'
        - '\wwahost.exe'
filter_main_legit_sndvol:
    Image|endswith: '\sndvol.exe'
    ParentCommandLine|contains: 'mmsys.cpl'
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

• Unlikely

Tags

• attack.privilege-escalation
• attack.stealth
• attack.t1055.012
• detection.emerging-threats

MITRE ATT&CK ids this rule names

• T1055.012

References

• https://www.virustotal.com/gui/file/b6e8910fb9b3bb1fcddefd35ff0ed8624930d30d6977e11808c8330415685a62
• https://www.virustotal.com/gui/file/6bb4cdbaef03b732a93559a58173e7f16b29bfb159a1065fae9185000ff23b4b
• https://github.com/pr0xylife/Pikabot/blob/7f7723a74ca325ec54c6e61e076acce9a4b20538/Pikabot_06.12.2023.txt

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2023/Malware/Pikabot/proc_creation_win_malware_pikabot_rundll32_hollowing.yml