Detection rules › Sigma
Suspicious CertReq Command to Download
Detects a suspicious CertReq execution downloading a file. This behavior is often used by attackers to download additional payloads or configuration files. Certreq is a built-in Windows utility used to request and retrieve certificates from a certification authority (CA). However, it can be abused by threat actors for malicious purposes.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control | T1105 Ingress Tool Transfer |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 1 | Process creation |
Stages and Predicates
Stage 1: all of selection_img
or:
Image|endswith: '\certreq.exe'
OriginalFileName: CertReq.exe
Stage 2: all of selection_cli_flag_post
CommandLine|contains: -Post
Stage 3: all of selection_cli_flag_config
CommandLine|contains: -config
Stage 4: all of selection_cli_http
CommandLine|contains: http
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 |
|
OriginalFileName | eq |
|