Sigma rule: Security Tools Keyword Lookup Via Findstr.EXE

Rule

Title

Security Tools Keyword Lookup Via Findstr.EXE

Status

test

Level

medium

Author

Nasreddine Bencherchali (Nextron Systems), frack113

Date

2023-10-20

Modified

2023-11-14

File

rules/windows/process_creation/proc_creation_win_findstr_security_keyword_lookup.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of "findstr" to search for common names of security tools. Attackers often pipe the results of recon commands such as "tasklist" or "whoami" to "findstr" in order to filter out the results.
This detection focuses on the keywords that the attacker might use as a filter.

Log source

product

windows

category

process_creation

Detection

selection_img:
    - Image|endswith:
          - '\find.exe'
          - '\findstr.exe'
    - OriginalFileName:
          - 'FIND.EXE'
          - 'FINDSTR.EXE'
selection_cli:
    CommandLine|endswith:
        # Note: Add additional keywords to increase and enhance coverage
        # Note:
        #   We use the double quote variation because in cases of where the command is executed through cmd for example:
        #       cmd /c "tasklist | findstr virus"
        #   Logging utilties such as Sysmon would capture the end quote as part of findstr execution
        - ' avira'
        - ' avira"'
        - ' cb'
        - ' cb"'
        - ' cylance'
        - ' cylance"'
        - ' defender'
        - ' defender"'
        - ' kaspersky'
        - ' kaspersky"'
        - ' kes'
        - ' kes"'
        - ' mc'
        - ' mc"'
        - ' sec'
        - ' sec"'
        - ' sentinel'
        - ' sentinel"'
        - ' symantec'
        - ' symantec"'
        - ' virus'
        - ' virus"'
condition: all of selection_*

False positives (as the rule lists them)

• Unknown

Tags

• attack.discovery
• attack.t1518.001

MITRE ATT&CK ids this rule names

• T1518.001

Related rules

• fe63010f-8823-4864-a96b-a7b4a0f7b929 (derived)

References

• https://github.com/redcanaryco/atomic-red-team/blob/987e3ca988ae3cff4b9f6e388c139c05bf44bbb8/atomics/T1518.001/T1518.001.md#atomic-test-1---security-software-discovery
• https://www.microsoft.com/en-us/security/blog/2023/10/18/multiple-north-korean-threat-actors-exploiting-the-teamcity-cve-2023-42793-vulnerability/
• https://www.hhs.gov/sites/default/files/manage-engine-vulnerability-sector-alert-tlpclear.pdf

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_findstr_security_keyword_lookup.yml