Sigma rule: Diskshadow Script Mode - Uncommon Script Extension Execution

Rule

Title

Diskshadow Script Mode - Uncommon Script Extension Execution

Status

test

Level

medium

Author

Nasreddine Bencherchali (Nextron Systems)

Date

2023-09-15

Modified

2024-03-05

File

rules/windows/process_creation/proc_creation_win_diskshadow_script_mode_susp_ext.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of "Diskshadow.exe" in script mode to execute an script with a potentially uncommon extension.
Initial baselining of the allowed extension list is required.

Log source

product

windows

category

process_creation

Detection

selection_img:
    - OriginalFileName: 'diskshadow.exe'
    - Image|endswith: '\diskshadow.exe'
selection_flag:
    CommandLine|contains|windash: '-s '
filter_main_ext:
    # Note: can be changed to an "endswith" to avoid rare FPs. But you need to account for quoted paths
    # Note: Using the ".txt" is based on the MS documentation example. Best add the extension you use internally before using this rule
    CommandLine|contains: '.txt'
condition: all of selection_* and not 1 of filter_main_*

False positives (as the rule lists them)

• False postitve might occur with legitimate or uncommon extensions used internally. Initial baseline is required.

Tags

• attack.stealth
• attack.t1218

MITRE ATT&CK ids this rule names

• T1218

Related rules

• fa1a7e52-3d02-435b-81b8-00da14dd66c1 (similar)
• 9f546b25-5f12-4c8d-8532-5893dcb1e4b8 (similar)
• 56b1dde8-b274-435f-a73a-fb75eb81262a (similar)
• 0c2f8629-7129-4a8a-9897-7e0768f13ff2 (similar)

References

• https://bohops.com/2018/03/26/diskshadow-the-return-of-vss-evasion-persistence-and-active-directory-database-extraction/
• https://www.ired.team/offensive-security/credential-access-and-credential-dumping/ntds.dit-enumeration
• https://medium.com/@cyberjyot/lolbin-execution-via-diskshadow-f6ff681a27a4
• https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/diskshadow
• https://www.lifars.com/wp-content/uploads/2022/01/GriefRansomware_Whitepaper-2.pdf
• https://www.zscaler.com/blogs/security-research/technical-analysis-crytox-ransomware
• https://research.checkpoint.com/2022/evilplayout-attack-against-irans-state-broadcaster/

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/process_creation/proc_creation_win_diskshadow_script_mode_susp_ext.yml