{"id":"CVE-2021-38195","aliases":["EUVD-2021-1711","GHSA-g4vj-x7v9-h82m","RUSTSEC-2021-0076"],"status":"published","title":"Overflow in libsecp256k1","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.00909,"percentile":0.60434,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-190","CWE-347"],"published":"2021-07-13T12:00:00Z","modified":"2026-11-03T02:30:33Z","fixes":[{"ecosystem":"crates.io","package":"libsecp256k1","fixed_in":["0.5.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"libsecp256k1","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.5.0"}]}]},{"source":"osv","ecosystem":"crates.io","package":"libsecp256k1","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.5.0"}]}]},{"source":"osv","ecosystem":"crates.io","package":"libsecp256k1","ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"0.5.0"}]}]}],"products":[{"vendor":"parity","product":"libsecp256k1"}],"references":[{"url":"https://rustsec.org/advisories/RUSTSEC-2021-0076.html","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Patch","Third Party Advisory","fix","web","advisory"]},{"url":"https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/libsecp256k1/RUSTSEC-2021-0076.md","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-38195","tags":["advisory"]},{"url":"https://github.com/paritytech/libsecp256k1/pull/67","tags":["web"]},{"url":"https://github.com/advisories/GHSA-g4vj-x7v9-h82m"},{"url":"https://github.com/paritytech/libsecp256k1","tags":["package"]},{"url":"https://crates.io/crates/libsecp256k1","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2021-38195","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-08T05:07:36Z","modified":"2024-08-04T01:37:16.09Z","updated_at":"2026-11-02T14:33:07.697752Z"}],"euvd":[{"id":"EUVD-2021-1711","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-08T05:07:36Z","modified":"2024-08-04T01:37:16Z","updated_at":"2026-11-03T03:24:25.244479Z"}],"ghsa":[{"id":"GHSA-g4vj-x7v9-h82m","title":"Overflow in libsecp256k1","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-25T20:56:03Z","modified":"2023-02-03T05:06:15Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-190","CWE-347"],"updated_at":"2026-11-02T14:36:43.439065Z"}],"nvd":[{"id":"CVE-2021-38195","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-08T06:15:09.117Z","modified":"2026-06-17T04:01:44.243Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:06:56.562207Z"}],"osv":[{"id":"CVE-2021-38195","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-08T06:15:09.117Z","modified":"2026-11-03T02:30:33.281312929Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-03T03:05:53.289262Z"},{"id":"GHSA-g4vj-x7v9-h82m","title":"Overflow in libsecp256k1","description":"An issue was discovered in the libsecp256k1 crate before 0.5.0 for Rust. It can verify an invalid signature because it allows the R or S parameter to be larger than the curve order, aka an overflow.","status":"published","published":"2021-08-25T20:56:03Z","modified":"2023-11-08T04:06:26.227511Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-190","CWE-347"],"updated_at":"2026-11-02T15:46:47.119724Z"},{"id":"RUSTSEC-2021-0076","title":"libsecp256k1 allows overflowing signatures","description":"libsecp256k1 accepts signatures whose R or S parameter is larger than the\nsecp256k1 curve order, which differs from other implementations. This could\nlead to invalid signatures being verified.\n\nThe error is resolved in 0.5.0 by adding a `check_overflow` flag.","status":"published","published":"2021-07-13T12:00:00Z","modified":"2023-11-08T04:06:26.227511Z","updated_at":"2026-11-02T15:53:39.492624Z"}]}}