Detection rules › Sigma
Uncommon FileSystem Load Attempt By Format.com
Detects the execution of format.com with an uncommon filesystem selection that could indicate a defense evasion activity in which "format.com" is used to load malicious DLL files or other programs.
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 1 | Process creation |
| Security-Auditing | 4688 | A new process has been created. |
Stages and Predicates
Stage 1: selection
CommandLine|contains: '/fs:'
Image|endswith: '\format.com'
Stage 2: not 1 of filter_main_known_fs
or:
CommandLine|contains: '/fs:FAT'
CommandLine|contains: '/fs:NTFS'
CommandLine|contains: '/fs:ReFS'
CommandLine|contains: '/fs:UDF'
CommandLine|contains: '/fs:exFAT'
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 |
|---|---|---|
CommandLine | match |
|
Image | ends_with |
|