Starman vulnerabilities

Starman versions before 0.4019 for Perl allow memory exhaustion via unbounded buffering of chunked request bodies. The decoder does not limit chunk-size line length or buffer size. A remote attacker can exhaust worker memory with a single connection.

Starman versions before 0.4019 for Perl send response bodies for HEAD requests, desynchronizing responses on keep-alive connections. Bodies are also sent for 1xx, 204, and 304 statuses. A client or proxy may read those bytes as the start of the next response.

Starman versions before 0.4019 for Perl allow CPU exhaustion via quadratic regex backtracking when parsing chunked request bodies. A hex line followed by a bare LF and CRLF never matches, and each attempt backtracks quadratically. Line length is unbounded.

Starman versions before 0.4019 for Perl allow a stalled request body to hold a worker indefinitely, as read_timeout covers only headers. Bodies are read with blocking reads and no deadline. An attacker can occupy all workers with a few connections.

Starman for Perl before version 0.4018 is vulnerable to HTTP Request Smuggling due to improper header precedence. Starman incorrectly prioritizes Content-Length over Transfer-Encoding: chunked, violating RFC 7230. An attacker can exploit this to smuggle malicious HTTP requests through a front-end reverse proxy.