{"id":"DEBIAN-CVE-2026-45352","details":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.43.4, negative chunk-size in chunked Transfer-Encoding causes unbounded memory allocation and process crash. The ChunkedDecoder::read_payload function in cpp-httplib (httplib.h) parses the chunk-size field of HTTP chunked transfer encoding using std::strtoul(). Per the C standard (§7.22.1.4), strtoul silently accepts a leading minus sign, performing unsigned wrap-around: strtoul(\"-2\", …, 16) returns ULONG_MAX − 1 (0xFFFFFFFFFFFFFFFE). The library's only guard (line 12833) rejects ULONG_MAX (the result of \"-1\"), but any other negative value such as \"-2\" passes validation. The resulting near-maximum value is stored in chunk_remaining and controls how many bytes the server's read loop consumes from the network. This vulnerability is fixed in 0.43.4.","modified":"2026-09-14T17:03:13.390173843Z","published":"2026-05-29T20:16:26.140Z","upstream":["CVE-2026-45352"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-45352"}],"affected":[{"package":{"name":"cpp-httplib","ecosystem":"Debian:12","purl":"pkg:deb/debian/cpp-httplib?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.11.4+ds-1","0.11.4+ds-1+deb12u1","0.11.4+ds-2","0.11.4+ds-3","0.13.1+ds-1","0.14.0+ds-1","0.14.1+ds-1","0.14.1+ds-2","0.14.2+ds-1","0.14.3+ds-1","0.14.3+ds-1.1","0.14.3+ds-1.1~exp1","0.15.3+ds-1","0.15.3+ds-2","0.15.3+ds-3","0.16.0+ds-1","0.16.3+ds-1","0.16.3+ds-2","0.18.0+ds-1","0.18.7-1","0.20.1+ds-3","0.25.0+ds-1","0.26.0+ds-2","0.41.0+ds-1","0.41.0+ds-2","0.41.0+ds-3","0.41.0+ds-3~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45352.json"}},{"package":{"name":"cpp-httplib","ecosystem":"Debian:13","purl":"pkg:deb/debian/cpp-httplib?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.18.7-1","0.18.7-1+deb13u1","0.20.1+ds-3","0.25.0+ds-1","0.26.0+ds-2","0.41.0+ds-1","0.41.0+ds-2","0.41.0+ds-3","0.41.0+ds-3~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45352.json"}},{"package":{"name":"cpp-httplib","ecosystem":"Debian:14","purl":"pkg:deb/debian/cpp-httplib?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.18.7-1","0.20.1+ds-3","0.25.0+ds-1","0.26.0+ds-2","0.41.0+ds-1","0.41.0+ds-2","0.41.0+ds-3","0.41.0+ds-3~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-45352.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}