Possible Shellshock Exploitation Attempt via Web Request
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-10-17
- Updated
- 2026-10-17
ATT&CK techniques
Initial AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects Shellshock (CVE-2014-6271) exploitation attempts where the Bash function-definition prefix appears inside HTTP request fields such as the User-Agent, URI query or Referer against CGI endpoints. Observed in NCC Group research capturing Shellshock payloads that deliver shell download commands. Detecting these requests helps identify attempts to gain unauthenticated remote code execution on exposed servers.
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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