Lab: Blind OS command injection with out-of-band data exfiltration
Summary: PortSwigger's lab presents a blind OS command injection flaw in an application's feedback function, where user-supplied details are passed into a shell command that runs asynchronously and leaves no trace in the application's response. Because output cannot be redirected to an accessible location, the lab requires running the whoami command and exfiltrating the result through a DNS query to Burp Collaborator's default public server.
What's compelling: The command runs and the application's response never changes, so a working injection looks identical to normal behavior to anyone watching the page - the only evidence leaves your network as an outbound DNS lookup.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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