{"id":"CVE-2023-24533","aliases":["EUVD-2023-0995","GHSA-f6hc-9g49-xmx7","GO-2023-1595"],"status":"published","title":"Incorrect multiplication of unreduced P-256 scalars in filippo.io/nistec","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.00674,"percentile":0.5243,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-682"],"published":"2023-02-28T22:54:56Z","modified":"2026-10-28T02:31:01Z","fixes":[{"ecosystem":"Go","package":"filippo.io/nistec","fixed_in":["0.0.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"filippo.io/nistec","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.2"}]}]},{"source":"osv","ecosystem":"Go","package":"filippo.io/nistec","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.0.2"}]}]},{"source":"osv","ecosystem":"Go","package":"filippo.io/nistec","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.0.2"}]}]}],"products":[{"vendor":"filippo.io/nistec","product":"filippo.io/nistec"},{"vendor":"nistec_project","product":"nistec"}],"references":[{"url":"https://go.dev/issue/58647","tags":["x_transferred","Issue Tracking","Patch","web","report"]},{"url":"https://github.com/FiloSottile/nistec/commit/c58aa1223ccf3943513e1e661cebce95af137244","tags":["x_transferred","Patch","fix","web"]},{"url":"https://pkg.go.dev/vuln/GO-2023-1595","tags":["x_transferred","Third Party Advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-24533","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-f6hc-9g49-xmx7"},{"url":"https://pkg.go.dev","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/24xxx/CVE-2023-24533.json","tags":["advisory"]},{"url":"https://github.com/FiloSottile/nistec","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2023-24533","title":"Incorrect multiplication of unreduced P-256 scalars in filippo.io/nistec","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.","status":"published","published":"2023-03-08T19:40:38.341Z","modified":"2025-02-28T19:51:47.955Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"adp"}],"updated_at":"2026-11-02T14:35:27.006218Z"}],"euvd":[{"id":"EUVD-2023-0995","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.","status":"published","published":"2023-03-08T19:40:38Z","modified":"2025-02-28T19:51:47Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T20:53:19.492993Z"}],"ghsa":[{"id":"GHSA-f6hc-9g49-xmx7","title":"nistec has Incorrect Calculation in Multiplication of unreduced P-256 scalars","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.\n\nFrom the fix commit notes:\n\n\u003e Unlike the rest of nistec, the P-256 assembly doesn't use complete addition formulas, meaning that p256PointAdd[Affine]Asm won't return the correct value if the two inputs are equal.\n\u003e \n\u003e This was (undocumentedly) ignored in the scalar multiplication loops because as long as the input point is not the identity and the scalar is lower than the order of the group, the addition inputs can't be the same.\n\u003e \n\u003e As part of the math/big rewrite, we went however from always reducing the scalar to only checking its length, under the incorrect assumption that the scalar multiplication loop didn't require reduction.","status":"published","published":"2023-03-01T22:36:36Z","modified":"2024-05-20T21:48:50Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-682"],"updated_at":"2026-11-02T14:37:50.750599Z"}],"nvd":[{"id":"CVE-2023-24533","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.","status":"published","published":"2023-03-08T20:15:09.497Z","modified":"2026-06-17T05:39:28.73Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"primary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-682"],"updated_at":"2026-11-02T14:07:48.342507Z"}],"osv":[{"id":"CVE-2023-24533","title":"Incorrect multiplication of unreduced P-256 scalars in filippo.io/nistec","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.","status":"published","published":"2023-03-08T19:40:38.341Z","modified":"2026-10-28T02:31:01.752246483Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:30.709518Z"},{"id":"GHSA-f6hc-9g49-xmx7","title":"nistec has Incorrect Calculation in Multiplication of unreduced P-256 scalars","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.\n\nFrom the fix commit notes:\n\n\u003e Unlike the rest of nistec, the P-256 assembly doesn't use complete addition formulas, meaning that p256PointAdd[Affine]Asm won't return the correct value if the two inputs are equal.\n\u003e \n\u003e This was (undocumentedly) ignored in the scalar multiplication loops because as long as the input point is not the identity and the scalar is lower than the order of the group, the addition inputs can't be the same.\n\u003e \n\u003e As part of the math/big rewrite, we went however from always reducing the scalar to only checking its length, under the incorrect assumption that the scalar multiplication loop didn't require reduction.","status":"published","published":"2023-03-01T22:36:36Z","modified":"2024-05-20T21:48:49Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-682"],"updated_at":"2026-11-02T15:46:46.006631Z"},{"id":"GO-2023-1595","title":"Incorrect multiplication of unreduced P-256 scalars in filippo.io/nistec","description":"Multiplication of certain unreduced P-256 scalars produce incorrect results.\n\nThere are no protocols known at this time that can be attacked due to this.","status":"published","published":"2023-02-28T22:54:56Z","modified":"2024-05-20T16:03:47Z","updated_at":"2026-11-02T15:47:01.185262Z"}]}}