{"cve":"CVE-2021-38194","nvd":{"published":"2021-08-08T06:15:09.080","modified":"2026-06-17T04:01:44.123","status":"Modified","description":"An issue was discovered in the ark-r1cs-std crate before 0.3.1 for Rust. It does not enforce any constraints in the FieldVar::mul_by_inverse method. Thus, a prover can produce a proof that is unsound but is nonetheless verified.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":[],"references":["https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/ark-r1cs-std/RUSTSEC-2021-0075.md","https://rustsec.org/advisories/RUSTSEC-2021-0075.html","https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/ark-r1cs-std/RUSTSEC-2021-0075.md","https://rustsec.org/advisories/RUSTSEC-2021-0075.html"],"products":["arcworks:ark-r1cs-std"],"source":"nvd","synced_at":"2026-10-19T21:21:13.713336758+00:00"},"epss":{"cve":"CVE-2021-38194","score":0.01275,"percentile":0.69932,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-qj3v-q2vj-4c8h","url":"https://osv.dev/vulnerability/GHSA-qj3v-q2vj-4c8h","summary":"Calculation error in ark-r1cs-std","modified":"2023-11-08T04:06:26.167178Z","packages":[{"ecosystem":"crates.io","name":"ark-r1cs-std","purl":"pkg:cargo/ark-r1cs-std","ranges":[">=0.2.0 <0.3.1"],"fixed":["0.3.1"]}]},{"id":"RUSTSEC-2021-0075","url":"https://osv.dev/vulnerability/RUSTSEC-2021-0075","summary":"Flaw in `FieldVar::mul_by_inverse` allows unsound R1CS constraint systems","modified":"2023-11-08T04:06:26.167178Z","packages":[{"ecosystem":"crates.io","name":"ark-r1cs-std","purl":"pkg:cargo/ark-r1cs-std","ranges":[">=0.0.0-0 <0.3.1"],"fixed":["0.3.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}