{"id":"CVE-2026-11856","aliases":["CURL-CVE-2026-11856"],"url":"https://o3.security/vulnerability/CVE-2026-11856","summary":"cross-origin Digest auth state leak","details":"Successfully using libcurl to do a transfer to a specific HTTP origin\n(`hostA`) with **Digest** authentication and then changing the origin to a\ndifferent one (`hostB`) for a second transfer, reusing the same handle, makes\nlibcurl wrongly pass on the `Authorization:` header field meant for `hostA`,\nto `hostB`.","published":"2026-07-03T06:13:31.661Z","modified":"2026-09-22T12:41:42.255992480Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[],"fix":null,"references":[{"type":"WEB","url":"https://curl.se/docs/CVE-2026-11856.html"},{"type":"WEB","url":"https://curl.se/docs/CVE-2026-11856.json"},{"type":"WEB","url":"https://hackerone.com/reports/3793260"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/11xxx/CVE-2026-11856.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-11856"},{"type":"PACKAGE","url":"https://github.com/curl/curl.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-22T12:41:42.255992480Z"}}