{"id":"CVE-2026-69206","aliases":["GHSA-9xww-74xv-gjfp"],"url":"https://o3.security/vulnerability/CVE-2026-69206","summary":"Http4s: DigestAuth allows replay of captured requests","details":"The `DigestAuth` replay defence stores `lastNc + 1` rather than the nonce-count (`nc`) value it just accepted. When a legitimate client sends non-contiguous `nc` values (parallel or retried requests, as browsers do), the server's counter lags behind the highest `nc` seen, and a captured `Authorization` header can be replayed multiple times.\n\n## Impact\n\nA passive observer can turn one captured Digest-authenticated request into several replayed authenticated (state-changing) requests, defeating the core\nreplay protection Digest provides over Basic.\n\n## Preconditions\n\n- Application uses `DigestAuth`.\n- Attacker can passively observe at least one legitimate digest request.\n- Legitimate client emits an `nc` more than one greater than the last, for instance from a parallel or retried request.\n\n## Workarounds\n\n- Deploy over TLS so requests cannot be captured.","published":"2026-09-15T19:29:40.341Z","modified":"2026-10-28T02:30:28.996336950Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":{"score":0.00326,"percentile":0.25747,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.http4s:http4s-ember-core_2.12","fixedVersion":"0.23.35"},{"ecosystem":"Maven","name":"org.http4s:http4s-ember-core_2.13","fixedVersion":"0.23.35"},{"ecosystem":"Maven","name":"org.http4s:http4s-ember-core_3","fixedVersion":"0.23.35"},{"ecosystem":"Maven","name":"org.http4s:http4s-ember-core_2.13","fixedVersion":"1.0.0-M47"},{"ecosystem":"Maven","name":"org.http4s:http4s-ember-core_3","fixedVersion":"1.0.0-M47"}],"fix":{"url":"https://github.com/http4s/http4s/commit/7f065101c45f3d86bc105e8fc6323c2c4a11471f","label":"http4s/http4s@7f06510"},"references":[{"type":"WEB","url":"https://github.com/http4s/http4s/releases/tag/v0.23.35"},{"type":"WEB","url":"https://github.com/http4s/http4s/releases/tag/v1.0.0-M47"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69206.json"},{"type":"ADVISORY","url":"https://github.com/http4s/http4s/security/advisories/GHSA-9xww-74xv-gjfp"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-69206"},{"type":"FIX","url":"https://github.com/http4s/http4s/commit/7f065101c45f3d86bc105e8fc6323c2c4a11471f"},{"type":"PACKAGE","url":"https://github.com/http4s/http4s"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:28.996336950Z"}}