Sigma rule: Suspicious GrpConv Execution

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-54ffb1686f4c, updated 2022-05-19T00:00:00.000Z.

Rule

Title
Suspicious GrpConv Execution
Status
test
Level
high
Author
Florian Roth (Nextron Systems)
Date
2022-05-19
File
rules/windows/process_creation/proc_creation_win_lolbin_susp_grpconv.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the suspicious execution of a utility to convert Windows 3.x .grp files or for persistence purposes by malicious software or actors

Log source

product
windows
category
process_creation

Detection

selection:
    CommandLine|contains:
        - 'grpconv.exe -o'
        - 'grpconv -o'
condition: selection

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.privilege-escalation
  • attack.persistence
  • attack.t1547

MITRE ATT&CK ids this rule names

References

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_lolbin_susp_grpconv.yml

Sources and licences

  • SigmaHQ

    "Suspicious GrpConv Execution" by Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_lolbin_susp_grpconv.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Suspicious GrpConv Execution",
entity page, dataset version ref-54ffb1686f4c, updated 2022-05-19T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/f14e169e-9978-4c69-acb3-1cff8200bc36 (accessed 2026-11-03).
Underlying source: SigmaHQ rule f14e169e-9978-4c69-acb3-1cff8200bc36, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.