ghsa-w5vr-6qhr-36cc
Vulnerability from github
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.
Such 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.
Unfortunately, when this happens, one can easily extract the private key.
Revised 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.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "ed25519-dalek"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2022-50237"
],
"database_specific": {
"cwe_ids": [
"CWE-497"
],
"github_reviewed": true,
"github_reviewed_at": "2023-08-14T21:10:29Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"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.",
"id": "GHSA-w5vr-6qhr-36cc",
"modified": "2025-07-28T15:53:32Z",
"published": "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"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "`ed25519-dalek` Double Public Key Signing Function Oracle Attack"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.