Possible Shellshock Bash Function Definition Injection via Process Creation

ATT&CK techniques

Initial Access → Execution

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
- T1059.004Unix Shell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the Shellshock (CVE-2014-6271) exploitation pattern where an attacker injects a Bash environment-variable function definition prefix into a command line. Captured in NCC Group research on the Shellshock Bash vulnerability targeting CGI endpoints. Exploiting this flaw yields unauthenticated remote code execution which makes early detection of the injection prefix important.

Reporting behind it

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Possible Shellshock Bash Function Definition Injection via Process Creation

Pivot detection · T1059.004 · 9 related

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