Detection rules › Sigma

Remote File Download Via Desktopimgdownldr Utility

Severity
medium
Author
Tim Rauch, Elastic (idea)
Source
upstream

Detects the desktopimgdownldr utility being used to download a remote file. An adversary may use desktopimgdownldr to download arbitrary files as an alternative to certutil.

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1105 Ingress Tool Transfer

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.

Stages and Predicates

Stage 1: selection

CommandLine|contains: '/lockscreenurl:http'
Image|endswith: '\desktopimgdownldr.exe'
ParentImage|endswith: '\desktopimgdownldr.exe'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • /lockscreenurl:http
Imageends_with
  • \desktopimgdownldr.exe
ParentImageends_with
  • \desktopimgdownldr.exe