BCheck definition reference - Port Swigger

Summary: PortSwigger's reference page documents the keywords available for writing a BCheck, the declarative scan check definition language used by Burp Scanner, with mandatory properties such as language (currently enum v2-beta) and name marked by an asterisk. The page details control flow keywords including given...then, run for each, define, if, else if and else, action keywords for sending requests and reporting issues, and functions such as {random_str(int)}, regex_replace, to_lower and to_upper.
Why it matters: BChecks let teams codify their own vulnerability checks inside Burp Scanner, and the reference notes that all issues reported by BChecks carry the issue type Declarative Scan Check Generated and are consolidated only when reported by the same BCheck with the same name - so naming and structure decisions directly shape what your scanner surfaces and how much duplicate noise reaches triage.

Read the original at PortSwigger Research ↗

Topics: Vulnerabilities & Patching
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