Detection rules › Sigma

VMMap Signed Dbghelp.DLL Potential Sideloading

Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects potential DLL sideloading of a signed dbghelp.dll by the Sysinternals VMMap.

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1574.001 Hijack Execution Flow: DLL
Privilege EscalationT1574.001 Hijack Execution Flow: DLL
Defense EvasionT1574.001 Hijack Execution Flow: DLL

Event coverage

ProviderEvent IDTitle
Sysmon7Image loaded

Stages and Predicates

Stage 1: selection

or:
Image|endswith: '\vmmap.exe'
Image|endswith: '\vmmap64.exe'
ImageLoaded|contains: 'C:\Debuggers\dbghelp.dll'
Signed: true

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
Imageends_with
  • \vmmap.exe corpus 3 (sigma 3)
  • \vmmap64.exe corpus 3 (sigma 3)
ImageLoadedmatch
  • C:\Debuggers\dbghelp.dll corpus 2 (sigma 2)
Signedeq
  • true corpus 8 (sigma 8)

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.