Microsoft Excel Add-In Loaded From Uncommon Location

Severity: medium
Author: Nasreddine Bencherchali (Nextron Systems)
Source: upstream

Detects Microsoft Excel loading an Add-In (.xll) file from an uncommon location

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1204.002` User Execution: Malicious File

Event coverage

Provider	Event ID	Title
Sysmon	7	Image loaded

Stages and Predicates

Stage 1: `selection`

or:
ImageLoaded|contains: '\Desktop\'
ImageLoaded|contains: '\Downloads\'
ImageLoaded|contains: '\Perflogs\'
ImageLoaded|contains: '\Temp\'
ImageLoaded|contains: '\Users\Public\'
ImageLoaded|contains: '\Windows\Tasks\'
Image|endswith: '\excel.exe'
ImageLoaded|endswith: .xll

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.