{"id":"CVE-2026-33745","aliases":["DEBIAN-CVE-2026-33745","EUVD-2026-16515","GHSA-6hrp-7fq9-3qv2","OESA-2026-1867","OESA-2026-1868","OESA-2026-1869","OESA-2026-1870","UBUNTU-CVE-2026-33745","openSUSE-SU-2026:10573-1"],"status":"published","title":"cpp-httplib Client Leaks Authentication Credentials to Untrusted Hosts on Cross-Origin HTTP Redirect","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","severity":{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00266,"percentile":0.18861,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-200"],"published":"2026-03-27T00:46:48Z","modified":"2026-10-28T02:31:12Z","fixes":[{"ecosystem":"Debian:14","package":"cpp-httplib","fixed_in":["0.41.0+ds-3"],"sources":["osv"]}],"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"},{"fixed":"0.41.0+ds-3"}]}],"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~bpo13+1"]},{"source":"osv","ecosystem":"openEuler:24.03-LTS","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.40.0-1.oe2403"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP1","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.40.0-1.oe2403sp1"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP2","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.40.0-1.oe2403sp2"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP3","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.40.0-1.oe2403sp3"}]}],"bundled":2},{"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:25.10","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.18.7-1","0.18.7-1ubuntu0.25.10.1","0.18.7-1ubuntu0.25.10.2"]},{"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"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"cpp-httplib","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.42.0-1.1"}]}],"bundled":2}],"products":[{"vendor":"yhirose","product":"cpp-httplib"}],"references":[{"url":"https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-6hrp-7fq9-3qv2","tags":["x_refsource_CONFIRM","Exploit","Mitigation","Vendor Advisory","advisory","report"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33745.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33745","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-33745","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1867","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34441","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1868","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1869","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1870","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-33745","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-33745","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2026-33745","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-34441","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2026-33745","title":"cpp-httplib Client Leaks Authentication Credentials to Untrusted Hosts on Cross-Origin HTTP Redirect","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T00:46:48.941Z","modified":"2026-04-01T03:55:22.387Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T14:20:07.609948Z"}],"euvd":[{"id":"EUVD-2026-16515","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T00:46:48Z","modified":"2026-04-01T03:55:22Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T19:25:24.493801Z"}],"nvd":[{"id":"CVE-2026-33745","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T01:16:21.167Z","modified":"2026-06-17T10:38:01.593Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"primary"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T14:12:11.678711Z"}],"osv":[{"id":"CVE-2026-33745","title":"cpp-httplib Client Leaks Authentication Credentials to Untrusted Hosts on Cross-Origin HTTP Redirect","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T00:46:48.941Z","modified":"2026-10-28T02:31:12.746047878Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T15:45:01.896044Z"},{"id":"DEBIAN-CVE-2026-33745","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T01:16:21.167Z","modified":"2026-10-01T03:03:22.029746511Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:54.587575Z"},{"id":"OESA-2026-1867","title":"cpp-httplib security update","description":"A C++11 single-file header-only cross platform HTTP/HTTPS library. It\u0026amp;apos;s extremely easy to setup. Just include httplib.h file in your code!\r\n\r\nSecurity Fix(es):\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.(CVE-2026-33745)\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server\u0026apos;s static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive connections, the unread body bytes remain on the TCP stream and are interpreted as the start of a new HTTP request. An attacker can embed an arbitrary HTTP request inside the body of a GET request, which the server processes as a separate request. This issue has been patched in version 0.40.0.(CVE-2026-34441)","status":"published","published":"2026-04-11T11:10:53Z","modified":"2026-08-18T01:19:46.978460601Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:46.087701Z"},{"id":"OESA-2026-1868","title":"cpp-httplib security update","description":"A C++11 single-file header-only cross platform HTTP/HTTPS library. It\u0026amp;apos;s extremely easy to setup. Just include httplib.h file in your code!\r\n\r\nSecurity Fix(es):\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.(CVE-2026-33745)\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server\u0026apos;s static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive connections, the unread body bytes remain on the TCP stream and are interpreted as the start of a new HTTP request. An attacker can embed an arbitrary HTTP request inside the body of a GET request, which the server processes as a separate request. This issue has been patched in version 0.40.0.(CVE-2026-34441)","status":"published","published":"2026-04-11T11:10:53Z","modified":"2026-08-18T01:19:46.86127261Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:46.087701Z"},{"id":"OESA-2026-1869","title":"cpp-httplib security update","description":"A C++11 single-file header-only cross platform HTTP/HTTPS library. It\u0026amp;apos;s extremely easy to setup. Just include httplib.h file in your code!\r\n\r\nSecurity Fix(es):\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.(CVE-2026-33745)\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server\u0026apos;s static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive connections, the unread body bytes remain on the TCP stream and are interpreted as the start of a new HTTP request. An attacker can embed an arbitrary HTTP request inside the body of a GET request, which the server processes as a separate request. This issue has been patched in version 0.40.0.(CVE-2026-34441)","status":"published","published":"2026-04-11T11:10:53Z","modified":"2026-08-18T01:19:46.946181264Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:46.087701Z"},{"id":"OESA-2026-1870","title":"cpp-httplib security update","description":"A C++11 single-file header-only cross platform HTTP/HTTPS library. It\u0026amp;apos;s extremely easy to setup. Just include httplib.h file in your code!\r\n\r\nSecurity Fix(es):\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.(CVE-2026-33745)\n\ncpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.40.0, cpp-httplib is vulnerable to HTTP Request Smuggling. The server\u0026apos;s static file handler serves GET responses without consuming the request body. On HTTP/1.1 keep-alive connections, the unread body bytes remain on the TCP stream and are interpreted as the start of a new HTTP request. An attacker can embed an arbitrary HTTP request inside the body of a GET request, which the server processes as a separate request. This issue has been patched in version 0.40.0.(CVE-2026-34441)","status":"published","published":"2026-04-11T11:10:53Z","modified":"2026-08-18T01:19:45.938832798Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:46.087701Z"},{"id":"UBUNTU-CVE-2026-33745","description":"cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.","status":"published","published":"2026-03-27T01:16:00Z","modified":"2026-10-17T13:00:00.780304197Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"},{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T16:56:16.036833Z"},{"id":"openSUSE-SU-2026:10573-1","title":"cpp-httplib-devel-0.42.0-1.1 on GA media","description":"These are all security issues fixed in the cpp-httplib-devel-0.42.0-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-04-18T00:00:00Z","modified":"2026-04-19T10:30:32.26977Z","updated_at":"2026-11-02T16:58:38.415593Z"}]}}