{"id":"GHSA-w5vr-6qhr-36cc","summary":"`ed25519-dalek` Double Public Key Signing Function Oracle Attack","details":"Versions of `ed25519-dalek` prior to v2.0 model private and public keys as separate types which can be assembled into a `Keypair`, and also provide APIs for serializing and deserializing 64-byte private/public keypairs.\n\nSuch APIs and serializations are inherently unsafe as the public key is one of the inputs used in the deterministic computation of the `S` part of the signature, but not in the `R` value. An adversary could somehow use the signing function as an oracle that allows arbitrary public keys as input can obtain two signatures for the same message sharing the same `R` and only differ on the `S` part.\n\nUnfortunately, when this happens, one can easily extract the private key.\n\nRevised public APIs in v2.0 of `ed25519-dalek` do NOT allow a decoupled private/public keypair as signing input, except as part of specially labeled \"hazmat\" APIs which are clearly labeled as being dangerous if misused.","aliases":["CVE-2022-50237","RUSTSEC-2022-0093"],"modified":"2026-02-04T03:12:24.206854Z","published":"2023-08-14T21:10:29Z","related":["HSEC-2025-0002"],"database_specific":{"nvd_published_at":null,"cwe_ids":["CWE-497"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2023-08-14T21:10:29Z"},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-50237"},{"type":"WEB","url":"https://github.com/MystenLabs/ed25519-unsafe-libs"},{"type":"PACKAGE","url":"https://github.com/dalek-cryptography/ed25519-dalek"},{"type":"WEB","url":"https://rustsec.org/advisories/RUSTSEC-2022-0093.html"}],"affected":[{"package":{"name":"ed25519-dalek","ecosystem":"crates.io","purl":"pkg:cargo/ed25519-dalek"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.0.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/08/GHSA-w5vr-6qhr-36cc/GHSA-w5vr-6qhr-36cc.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N"}]}