CmdID / Rules / Windows

Potential Data Exfiltration Via Curl.EXE

A Sigma rule for process creation on Windows, from SigmaHQ’s threat hunting rules, by Florian Roth (Nextron Systems), Cedric MAURUGEON (Update).

medium 2 ATT&CK techniques 1 program it names

What it looks for

its detection, as SigmaHQ writes it

detection:
  filter_optional_localhost:
    CommandLine|contains:
      - '://localhost'
      - '://127.0.0.1'
  selection_cli:
    - CommandLine|contains:
        - ' --form'
        - ' --upload-file '
        - ' --data '
        - ' --data-'
    - CommandLine|re: '\s-[FTd]\s'
  selection_img:
    - Image|endswith: '\curl.exe'
    - Product: 'The curl executable'
  condition: all of selection_* and not 1 of filter_optional_*

The rule’s detection, its selections and fields in order of name. The whole rule, with its references and false positives, is on SigmaHQ, by Florian Roth (Nextron Systems), Cedric MAURUGEON (Update), under the Detection Rule License 1.1. CmdID evaluates it on a command line alone: a test on what a command line cannot show, such as the parent process or the user, is not met.

None of the everyday examples and documented commands on CmdID’s program pages trips it. To see whether a command line does, paste it into CmdID.

Programs and files it names

their pages here

curl.exe

ATT&CK

the techniques it is tagged with

T1105Ingress Tool Transfer

T1567Exfiltration Over Web Service

Potential Data Exfiltration Via Curl.EXE

What it looks for

Programs and files it names

ATT&CK

Other rules for T1105 Ingress Tool Transfer