{"id":"CVE-2026-8927","aliases":["CURL-CVE-2026-8927"],"url":"https://o3.security/vulnerability/CVE-2026-8927","summary":"env-set cross-proxy Digest auth state leak","details":"When reusing a libcurl handle for sequential transfers driven by\nenvironment-variable proxy configuration, libcurl fails to clear the proxy\nauthentication state between requests. Specifically, if the initial transfer\nauthenticates against `proxyA` using Digest auth, a subsequent transfer routed\nthrough `proxyB` erroneously leaks the `Proxy-Authorization:` header intended\nsolely for `proxyA`.","published":"2026-07-03T06:16:06.376Z","modified":"2026-08-18T12:26:56.248995101Z","cvss":{"score":9.1,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":{"score":0.0044,"percentile":0.36424,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[],"fix":null,"references":[{"type":"WEB","url":"https://curl.se/docs/CVE-2026-8927.html"},{"type":"WEB","url":"https://curl.se/docs/CVE-2026-8927.json"},{"type":"WEB","url":"https://hackerone.com/reports/3744543"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8927.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-8927"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T12:26:56.248995101Z"}}