{"id":"GHSA-c7jm-38gq-h67h","aliases":[],"url":"https://o3.security/vulnerability/GHSA-c7jm-38gq-h67h","summary":"http4k: `ServerFilters.DigestAuth` / `DigestAuthProvider` defaulted to an always-true nonce verifier, disabling replay protection in default deployments","details":"### Impact\n\n`ServerFilters.DigestAuth` and the underlying `DigestAuthProvider` both defaulted their `nonceVerifier` parameter to `{ true }` — i.e. every nonce was accepted regardless of value, age, or prior use. Any deployment using the default configuration had **no replay protection** on Digest authentication; a captured `Authorization: Digest …` response could be replayed indefinitely against the same protected resource.\n\nThe nonce-verification mechanism in Digest auth is the primary anti-replay control — without it, Digest reduces to a credential bound only to a stale nonce string.\n\n**Who is affected:** any application using `ServerFilters.DigestAuth` or `DigestAuthProvider` with the default `nonceVerifier`. The broken default has been present since `DigestAuthProvider` was introduced (2021). Exploitation requires the attacker to first capture a valid Digest response (network observation, log access, etc.) — non-trivial in modern TLS deployments but not impossible. Anyone running Digest auth with default config should treat upgrade as urgent.\n\n### Patches\n\n| Line | Fixed in | Edition |\n|------|----------|---------|\n| v6.x (Community) | **6.48.0.0** | Community |\n| v5.x (LTS) | **5.42.0.0** | Enterprise — contact [enterprise@http4k.org](mailto:enterprise@http4k.org) (if Digest auth is present in your v5.x line) |\n| v4.x (LTS) | **4.51.0.0** | Enterprise — contact [enterprise@http4k.org](mailto:enterprise@http4k.org) (if Digest auth is present in your v4.x line) |\n\nThe fix (`[Break]`) removes the default value for `nonceVerifier` from both `ServerFilters.DigestAuth` and `DigestAuthProvider`. Callers must now supply a real verifier explicitly — the broken default cannot be silently inherited.\n\n### Workarounds\n\nFor deployments that cannot upgrade immediately: explicitly supply a `nonceVerifier` that tracks issued nonces, enforces a TTL, and rejects re-use. Do not rely on the default.","published":"2026-06-19T21:16:09Z","modified":"2026-06-19T21:30:11.666403522Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.http4k:http4k-security-digest","fixedVersion":"6.48.0.0"},{"ecosystem":"Maven","name":"org.http4k:http4k-security-digest","fixedVersion":"5.42.0.0"},{"ecosystem":"Maven","name":"org.http4k:http4k-security-digest","fixedVersion":"4.51.0.0"}],"fix":{"url":"https://github.com/http4k/http4k/commit/4f904b4692","label":"http4k/http4k@4f904b4"},"references":[{"type":"WEB","url":"https://github.com/http4k/http4k/security/advisories/GHSA-c7jm-38gq-h67h"},{"type":"WEB","url":"https://github.com/http4k/http4k/commit/4f904b4692"},{"type":"WEB","url":"https://github.com/http4k/http4k/commit/8a52b615b1"},{"type":"WEB","url":"https://datatracker.ietf.org/doc/html/rfc7616#section-3.4"},{"type":"PACKAGE","url":"https://github.com/http4k/http4k"},{"type":"WEB","url":"https://github.com/http4k/http4k/releases/tag/6.48.0.0"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-06-19T21:30:11.666403522Z"}}