uhttpd is a small HTTP server. In unpatched repository snapshots, "client_parse_header()" in "client.c" lowercases header names but compares the "Transfer-Encoding" value to "chunked" using case-sensitive "strcmp". A mixed-case transfer-coding token is accepted without enabling "r->transfer_chunked", despite transfer-coding tokens being case-insensitive. On a keep-alive connection, the "chunked" POST body is left unread and request-shaped body bytes are parsed as another HTTP request, permitting HTTP request smuggling and boundary desynchronization. Commits ae015e099986ceace44975cb69629841a2d58d37 and 6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837 patch the issue.