{"id":"GHSA-56wv-2wr9-3h9r","summary":"Improper Verification of Cryptographic Signature in fastecdsa","details":"An issue was discovered in fastecdsa before 2.1.2. When using the NIST P-256 curve in the ECDSA implementation, the point at infinity is mishandled. This means that for an extreme value in k and s\u003csup\u003e-1\u003c/sup\u003e, the signature verification fails even if the signature is correct. This behavior is not solely a usability problem. There are some threat models where an attacker can benefit by successfully guessing users for whom signature verification will fail.","aliases":["CVE-2020-12607","PYSEC-2020-42"],"modified":"2025-02-12T18:47:08.220015Z","published":"2021-10-12T16:30:37Z","database_specific":{"github_reviewed_at":"2021-10-08T22:28:23Z","nvd_published_at":"2020-06-02T21:15:00Z","cwe_ids":["CWE-347"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-12607"},{"type":"WEB","url":"https://github.com/AntonKueltz/fastecdsa/issues/52"},{"type":"WEB","url":"https://github.com/AntonKueltz/fastecdsa/commit/4a16daeaf139be20654ef58a9fe4c79dc030458c"},{"type":"WEB","url":"https://github.com/AntonKueltz/fastecdsa/commit/7b64e3efaa806b4daaf73bb5172af3581812f8de"},{"type":"WEB","url":"https://github.com/AntonKueltz/fastecdsa/commit/e592f106edd5acf6dacedfab2ad16fe6c735c9d1"},{"type":"PACKAGE","url":"https://github.com/AntonKueltz/fastecdsa"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-56wv-2wr9-3h9r"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/fastecdsa/PYSEC-2020-42.yaml"}],"affected":[{"package":{"name":"fastecdsa","ecosystem":"PyPI","purl":"pkg:pypi/fastecdsa"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.2"}]}],"versions":["1.0.0b1","1.0.1","1.0.1b1","1.0.1b2","1.0.1b3","1.0.2","1.0.3","1.1.0","1.1.1","1.1.2","1.1.3","1.2.1","1.3.1","1.3.2","1.4.1","1.4.2","1.4.3","1.5.1","1.5.2","1.6.1","1.6.2","1.6.3","1.6.4","1.6.5","1.7.0","1.7.1","1.7.2","1.7.3","1.7.4","1.7.5","2.0.0","2.1.0","2.1.1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/10/GHSA-56wv-2wr9-3h9r/GHSA-56wv-2wr9-3h9r.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"}]}