pupnp is an SDK for development of UPnP device and control point applications. Prior to 22.0.4, parse_hostport in upnp/src/genlib/net/uri/uri.c synchronously calls getaddrinfo while parse_uri is processing attacker-supplied hostnames from inbound HTTP request targets in upnp/src/genlib/net/http/httpparser.c and GENA SUBSCRIBE CALLBACK headers handled by create_url_list in upnp/src/gena/gena_device.c. A remote unauthenticated peer can choose a slow or nonresponsive hostname and block a bounded miniserver worker for the resolver timeout, allowing a small number of requests to exhaust the thread pool and deny UPnP service. This issue is fixed in 22.0.4.
https://issues.oss-fuzz.com/issues/531780528
https://github.com/pupnp/pupnp/security/advisories/GHSA-46ph-jff5-5h77
https://github.com/pupnp/pupnp/releases/tag/release-22.0.4
https://github.com/pupnp/pupnp/commit/5dba8070b4d64d976f8e6fc13f1f301befebe7d2