Malicious Curl Download From C2 CAPTCHA Path via Process Creation
- Product
- windows
- Category
- process_creation
- Author
- HuntRule
- Published
- 2026-08-25
- Updated
- 2026-08-28
ATT&CK techniques
C2Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
Exfiltration
Impact
What it detects
This rule detects curl.exe retrieving a payload using the misspelled /capcha URL path pattern used by the KongTuke fake-CAPTCHA campaign documented by Cisco Talos. The tool is invoked by a PowerShell downloader to pull the next stage from hardcoded command-and-control infrastructure. Detecting it identifies active second-stage retrieval over an attacker-controlled channel.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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