Failed Code Integrity Checks

Severity: informational
Author: Thomas Patzke
Source: upstream

Detects code integrity failures such as missing page hashes or corrupted drivers due unauthorized modification. This could be a sign of tampered binaries.

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1027.001` Obfuscated Files or Information: Binary Padding

Event coverage

Provider	Event ID	Title
Security-Auditing	5038	Code integrity determined that the image hash of a file is not valid.
Security-Auditing	6281	Code Integrity determined that the page hashes of an image file are not valid.

Stages and Predicates

Stage 1: `selection`

Stage 2: `not 1 of filter_optional_*`

or:
param1|contains: '\CSFalconServiceUninstallTool_'
param1|contains: '\Program Files\CrowdStrike\'
param1|contains: '\Program Files\Sophos\'
param1|contains: '\System32\drivers\CrowdStrike\'
param1|contains: '\Windows\System32\ScriptControl64_'

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.

Field	Kind	Values
`param1`	match	`\CSFalconServiceUninstallTool_` `\Program Files\CrowdStrike\` `\Program Files\Sophos\` `\System32\drivers\CrowdStrike\` `\Windows\System32\ScriptControl64_`