Detection rules › Sigma

Mshtml.DLL RunHTMLApplication Suspicious Usage

Severity
high
Author
Nasreddine Bencherchali (Nextron Systems), Florian Roth (Nextron Systems), Josh Nickels, frack113, Zaw Min Htun (ZETA)
Source
upstream

Detects execution of commands that leverage the "mshtml.dll" RunHTMLApplication export to run arbitrary code via different protocol handlers (vbscript, javascript, file, http...)

Event coverage

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

Stages and Predicates

Stage 1: selection

or:
CommandLine|contains: '#135'
CommandLine|contains: RunHTMLApplication
CommandLine|contains: '\..\'
CommandLine|contains: mshtml

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
  • #135
  • RunHTMLApplication
  • \..\
  • mshtml