Detection rules › Sigma

Suspicious Usage Of ShellExec_RunDLL

Severity
high
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects suspicious usage of the ShellExec_RunDLL function to launch other commands as seen in the the raspberry-robin attack

Event coverage

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

Stages and Predicates

Stage 1: all of selection_openasrundll

CommandLine|contains: ShellExec_RunDLL

Stage 2: all of selection_suspcli

or:
CommandLine|contains: Invoke-
CommandLine|contains: '\Desktop\'
CommandLine|contains: '\Temp\'
CommandLine|contains: '\Users\Public\'
CommandLine|contains: comspec
CommandLine|contains: iex
CommandLine|contains: msiexec
CommandLine|contains: odbcconf
CommandLine|contains: regsvr32

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
  • Invoke- corpus 5 (sigma 5)
  • ShellExec_RunDLL corpus 2 (sigma 2)
  • \Desktop\ corpus 11 (sigma 11)
  • \Temp\ corpus 7 (sigma 7)
  • \Users\Public\ corpus 17 (sigma 17)
  • comspec
  • iex corpus 2 (sigma 2)
  • msiexec corpus 4 (sigma 4)
  • odbcconf
  • regsvr32 corpus 11 (sigma 11)