Sigma rule: Windows Spooler Service Suspicious Binary Load

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-9e2744b39e90, updated 2022-06-02T00:00:00.000Z.

Rule

Title
Windows Spooler Service Suspicious Binary Load
Status
test
Level
informational
Author
FPT.EagleEye, Thomas Patzke (improvements)
Date
2021-06-29
Modified
2022-06-02
File
rules-emerging-threats/2021/Exploits/CVE-2021-1675/image_load_exploit_cve_2021_1675_spoolsv_dll_load.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detect DLL Load from Spooler Service backup folder. This behavior has been observed during the exploitation of the Print Spooler Vulnerability CVE-2021-1675 and CVE-2021-34527 (PrinterNightmare).

Log source

product
windows
category
image_load

Detection

selection:
    Image|endswith: '\spoolsv.exe'
    ImageLoaded|contains:
        - '\Windows\System32\spool\drivers\x64\3\'
        - '\Windows\System32\spool\drivers\x64\4\'
    ImageLoaded|endswith: '.dll'
condition: selection

False positives (as the rule lists them)

  • Loading of legitimate driver

Tags

  • attack.persistence
  • attack.privilege-escalation
  • attack.execution
  • attack.stealth
  • attack.t1574
  • cve.2021-1675
  • cve.2021-34527
  • detection.emerging-threats

CVEs this rule names

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-emerging-threats/2021/Exploits/CVE-2021-1675/image_load_exploit_cve_2021_1675_spoolsv_dll_load.yml

Sources and licences

  • SigmaHQ

    "Windows Spooler Service Suspicious Binary Load" by FPT.EagleEye, Thomas Patzke (improvements) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2021/Exploits/CVE-2021-1675/image_load_exploit_cve_2021_1675_spoolsv_dll_load.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: Windows Spooler Service Suspicious Binary Load",
entity page, dataset version ref-9e2744b39e90, updated 2022-06-02T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/02fb90de-c321-4e63-a6b9-25f4b03dfd14 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 02fb90de-c321-4e63-a6b9-25f4b03dfd14, 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.