Burp Scanner error reference - Port Swigger
Summary: PortSwigger published a reference guide to the most common Burp Scanner error messages, covering causes such as server rate-limiting headers, out-of-scope redirects, failed login sequence replays, unparseable API definitions, and Burp's browser failing to launch in sandbox mode on Linux. It also documents errors where the scanner cannot connect to the Burp Collaborator server, causing OAST checks to be skipped, and where hostname resolution fails during the audit phase, which the guide attributes to intermittent network problems, server load, or web application firewalls blocking scan traffic.
What you should know: The guide states that scans may overload servers and that the resulting unusual activity can cause web application firewalls to start blocking requests, and that when the Collaborator server connection fails, OAST checks are skipped for the entire scan - meaning a scan can finish while silently missing a class of findings.
Read the original at PortSwigger Research ↗
- Topics
- Vulnerabilities & Patching
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