{"id":"CVE-2026-103930","aliases":["DEBIAN-CVE-2026-103930","EUVD-2026-101593","GHSA-vq69-f637-8fhr","UBUNTU-CVE-2026-103930"],"status":"published","title":"cpp-httplib open_stream serializes CRLF in request target into HTTP request line","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","severity":{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00366,"percentile":0.30892,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-113"],"published":"2026-10-14T18:19:38Z","modified":"2026-10-28T17:50:29Z","affected":[{"source":"osv","ecosystem":"Debian:12","package":"cpp-httplib","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"]},{"source":"osv","ecosystem":"Debian:13","package":"cpp-httplib","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"]},{"source":"osv","ecosystem":"Debian:14","package":"cpp-httplib","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"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.9.9+ds-1","0.9.10+ds-1","0.10.1+ds-1","0.10.2+ds-1","0.10.3+ds-1","0.10.3+ds-1ubuntu0.1~esm1","0.10.3+ds-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.13.1+ds-1ubuntu1","0.14.3+ds-1","0.14.3+ds-1.1","0.14.3+ds-1.1build1","0.14.3+ds-1.1build2","0.14.3+ds-1.1ubuntu0.1~esm1","0.14.3+ds-1.1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.26.0+ds-2ubuntu3","0.26.0+ds-2ubuntu4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.18.7-1","0.26.0+ds-2ubuntu2","0.26.0+ds-2ubuntu3","0.26.0+ds-2ubuntu3+esm1"]}],"products":[{"vendor":"yhirose","product":"cpp-httplib"}],"references":[{"url":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-vq69-f637-8fhr","tags":["x_refsource_CONFIRM","advisory","report"]},{"url":"https://github.com/yhirose/cpp-httplib/pull/2501","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/yhirose/cpp-httplib/commit/255c075b82cf9f221e6e607e8e6789e6e2bf4c2a","tags":["x_refsource_MISC","fix","report"]},{"url":"https://github.com/yhirose/cpp-httplib/releases/tag/v0.51.0","tags":["x_refsource_MISC","web","report"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103930.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-103930","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-103930","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-103930","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-103930","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-103930","title":"cpp-httplib open_stream serializes CRLF in request target into HTTP request line","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T18:19:38.256Z","modified":"2026-10-15T15:06:40.241Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"cna"}],"cwes":["CWE-113"],"updated_at":"2026-11-02T13:34:48.658051Z"}],"euvd":[{"id":"EUVD-2026-101593","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T18:19:38Z","modified":"2026-10-15T15:06:40Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T17:00:14.20041Z"}],"nvd":[{"id":"CVE-2026-103930","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T19:17:07.657Z","modified":"2026-10-16T20:04:29.76Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-113"],"updated_at":"2026-11-02T14:12:59.328869Z"}],"osv":[{"id":"CVE-2026-103930","title":"cpp-httplib open_stream serializes CRLF in request target into HTTP request line","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T18:19:38.256Z","modified":"2026-10-28T10:50:57.749788845Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"cwes":["CWE-113"],"updated_at":"2026-11-02T15:44:54.236592Z"},{"id":"DEBIAN-CVE-2026-103930","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T19:17:07.657Z","modified":"2026-10-23T17:47:45.513096186Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T15:45:48.903138Z"},{"id":"UBUNTU-CVE-2026-103930","description":"cpp-httplib is a C++ header-only HTTP/HTTPS library. From 0.29.0 until 0.51.0, Client::open_stream in httplib.h accepts a caller-controlled path that reaches detail::write_request_line() without the detail::encode_path() protection used by the ordinary buffered request path. Raw carriage-return and line-feed bytes in the path can therefore split the outbound HTTP/1.1 request line and inject attacker-shaped request metadata. Exploitation requires an embedding application to pass remote user input into the open_stream path and a backend or intermediary that interprets the injected bytes; the established impact is modification of backend-visible request data, not direct confidentiality or availability impact. This issue is fixed in version 0.51.0.","status":"published","published":"2026-10-14T19:17:00Z","modified":"2026-10-28T17:50:29Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T16:55:59.130573Z"}]}}