{"id":"RUSTSEC-2026-0240","summary":"Ed25519 identity public keys permit universal signature forgery","details":"All published versions of `dcrypt-sign` before 2.0.0 accepted the Edwards\nidentity as an Ed25519 public key. A signature with `R = B` and `S = 1` then\nverified for every message because the challenge term multiplied the identity.\nThe implementation also admitted other noncanonical or small-order inputs.\nConsumers that accepted externally supplied dcrypt Ed25519 keys may therefore\nhave accepted forged authorizations.\n\nVersion 2.0.0 replaces the custom arithmetic with `ed25519-dalek`, uses strict\nverification, and rejects noncanonical, small-order, and non-torsion-free public\nkeys and `R` values, as well as noncanonical `S \u003e= L`. No wrapper around the\naffected verifier is recommended as a complete workaround. Upgrade to 2.0.0 or\nlater, audit registered keys and trust stores, and review historical actions\nauthorized with externally supplied keys.","aliases":["GHSA-7j32-2mpw-c784"],"modified":"2026-08-09T12:45:02.621582115Z","published":"2026-08-09T12:00:00Z","database_specific":{"license":"CC0-1.0"},"references":[{"type":"PACKAGE","url":"https://crates.io/crates/dcrypt-sign"},{"type":"ADVISORY","url":"https://rustsec.org/advisories/RUSTSEC-2026-0240.html"},{"type":"ADVISORY","url":"https://github.com/ioi-foundation/dcrypt/security/advisories/GHSA-7j32-2mpw-c784"},{"type":"WEB","url":"https://github.com/ioi-foundation/dcrypt/commit/c99cc86f0ee353010cd202cbcd2c310371b0bbb8"},{"type":"WEB","url":"https://github.com/ioi-foundation/dcrypt/releases/tag/v2.0.0"}],"affected":[{"package":{"name":"dcrypt-sign","ecosystem":"crates.io","purl":"pkg:cargo/dcrypt-sign"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"2.0.0"}]}],"ecosystem_specific":{"affected_functions":null,"affects":{"arch":[],"os":[],"functions":[]}},"database_specific":{"categories":["crypto-failure"],"cvss":null,"informational":null,"source":"https://github.com/rustsec/advisory-db/blob/osv/crates/RUSTSEC-2026-0240.json"}}],"schema_version":"1.8.0"}