{"id":"CVE-2025-54873","aliases":["EUVD-2025-23666","GHSA-f6rc-24x4-ppxp"],"status":"published","title":"RISC Zero Underconstrained Vulnerability: Division","description":"RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions 2.0.0 through 2.1.0 and risc0-circuit-rv32im and risc0-circuit-rv32im-sys versions 2.0.0 through 2.0.4 contain vulnerabilities where signed integer division allows multiple outputs for certain inputs with only one being valid, and division by zero results are underconstrained. This issue is fixed in risc0-zkvm version 2.2.0 and version 3.0.0 for the  risc0-circuit-rv32im and risc0-circuit-rv32im-sys packages.","severity":{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.0044,"percentile":0.38526,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-369"],"published":"2025-08-05T17:42:06Z","modified":"2026-10-28T02:31:14Z","fixes":[{"ecosystem":"crates.io","package":"risc0-zkvm","fixed_in":["2.2.0"],"sources":["ghsa","osv"]},{"ecosystem":"crates.io","package":"risc0-circuit-rv32im","fixed_in":["3.0.0"],"sources":["ghsa","osv"]},{"ecosystem":"crates.io","package":"risc0-circuit-rv32im-sys","fixed_in":["3.0.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"risc0-zkvm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0"},{"fixed":"2.2.0"}]}]},{"source":"ghsa","ecosystem":"crates.io","package":"risc0-circuit-rv32im","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0"},{"fixed":"3.0.0"}]}]},{"source":"ghsa","ecosystem":"crates.io","package":"risc0-circuit-rv32im-sys","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0"},{"fixed":"3.0.0"}]}]},{"source":"osv","ecosystem":"crates.io","package":"risc0-zkvm","ranges":[{"type":"SEMVER","events":[{"introduced":"2.0.0"},{"fixed":"2.2.0"}]}]},{"source":"osv","ecosystem":"crates.io","package":"risc0-circuit-rv32im","ranges":[{"type":"SEMVER","events":[{"introduced":"2.0.0"},{"fixed":"3.0.0"}]}]},{"source":"osv","ecosystem":"crates.io","package":"risc0-circuit-rv32im-sys","ranges":[{"type":"SEMVER","events":[{"introduced":"2.0.0"},{"fixed":"3.0.0"}]}]}],"products":[{"vendor":"risc0","product":"risc0"}],"references":[{"url":"https://github.com/risc0/risc0/security/advisories/GHSA-f6rc-24x4-ppxp","tags":["x_refsource_CONFIRM","advisory","web"]},{"url":"https://github.com/risc0/risc0/pull/3235","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/risc0/zirgen/pull/249","tags":["x_refsource_MISC","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-54873","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-f6rc-24x4-ppxp"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/54xxx/CVE-2025-54873.json","tags":["advisory"]},{"url":"https://github.com/risc0/risc0","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2025-54873","title":"RISC Zero Underconstrained Vulnerability: Division","description":"RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions 2.0.0 through 2.1.0 and risc0-circuit-rv32im and risc0-circuit-rv32im-sys versions 2.0.0 through 2.0.4 contain vulnerabilities where signed integer division allows multiple outputs for certain inputs with only one being valid, and division by zero results are underconstrained. This issue is fixed in risc0-zkvm version 2.2.0 and version 3.0.0 for the  risc0-circuit-rv32im and risc0-circuit-rv32im-sys packages.","status":"published","published":"2025-08-05T23:35:09.208Z","modified":"2025-08-06T13:53:46.107Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low","assessor":"cna"}],"cwes":["CWE-369"],"updated_at":"2026-11-02T14:32:27.932735Z"}],"euvd":[{"id":"EUVD-2025-23666","description":"RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions 2.0.0 through 2.1.0 and risc0-circuit-rv32im and risc0-circuit-rv32im-sys versions 2.0.0 through 2.0.4 contain vulnerabilities where signed integer division allows multiple outputs for certain inputs with only one being valid, and division by zero results are underconstrained. This issue is fixed in risc0-zkvm version 2.2.0 and version 3.0.0 for the  risc0-circuit-rv32im and risc0-circuit-rv32im-sys packages.","status":"published","published":"2025-08-05T23:35:09Z","modified":"2025-08-06T13:53:46Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"updated_at":"2026-11-02T20:32:01.201967Z"}],"ghsa":[{"id":"GHSA-f6rc-24x4-ppxp","title":"RISC Zero Underconstrained Vulnerability: Division","description":"Two issues were found: For some inputs to signed integer division, the circuit allowed two outputs, only one of which was valid.  Additionally, the result of division by zero was underconstrained.\n\nThis vulnerability was identified using the Picus tool from Veridise. \n\nImpacted on-chain verifiers have already been disabled via the estop mechanism outlined in the [Verifier Management Design](https://github.com/risc0/risc0-ethereum/blob/release-2.0/contracts/version-management-design.md#base-verifier-implementations). \n\n## Mitigation\n\nWe recommend all impacted users upgrade as soon as possible.\n\nRust applications using the `risc0-zkvm` crate at versions \u003c 2.2 should upgrade to version 2.2.0 or later. \n\nSmart contract applications using the official [RISC Zero Verifier Router](https://dev.risczero.com/api/blockchain-integration/contracts/verifier#verifier-router) do not need to take any action: zkVM version 2.2 is active on all official routers, and version 2.1 has been disabled.\n\nSmart contract applications not using the verifier router should update their contracts to send verification calls to the 2.2 version of the verifier.","status":"published","published":"2025-08-05T17:42:06Z","modified":"2025-08-06T14:32:03Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"cwes":["CWE-369"],"updated_at":"2026-11-02T14:38:52.85141Z"}],"nvd":[{"id":"CVE-2025-54873","description":"RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions 2.0.0 through 2.1.0 and risc0-circuit-rv32im and risc0-circuit-rv32im-sys versions 2.0.0 through 2.0.4 contain vulnerabilities where signed integer division allows multiple outputs for certain inputs with only one being valid, and division by zero results are underconstrained. This issue is fixed in risc0-zkvm version 2.2.0 and version 3.0.0 for the  risc0-circuit-rv32im and risc0-circuit-rv32im-sys packages.","status":"published","published":"2025-08-06T00:15:31.523Z","modified":"2026-06-17T09:40:50.63Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low","assessor":"secondary"}],"cwes":["CWE-369"],"updated_at":"2026-11-02T14:11:22.319351Z"}],"osv":[{"id":"CVE-2025-54873","title":"RISC Zero Underconstrained Vulnerability: Division","description":"RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. RISC packages risc0-zkvm versions 2.0.0 through 2.1.0 and risc0-circuit-rv32im and risc0-circuit-rv32im-sys versions 2.0.0 through 2.0.4 contain vulnerabilities where signed integer division allows multiple outputs for certain inputs with only one being valid, and division by zero results are underconstrained. This issue is fixed in risc0-zkvm version 2.2.0 and version 3.0.0 for the  risc0-circuit-rv32im and risc0-circuit-rv32im-sys packages.","status":"published","published":"2025-08-05T23:35:09.208Z","modified":"2026-10-28T02:31:14.277434527Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"cwes":["CWE-369"],"updated_at":"2026-11-02T15:44:50.863921Z"},{"id":"GHSA-f6rc-24x4-ppxp","title":"RISC Zero Underconstrained Vulnerability: Division","description":"Two issues were found: For some inputs to signed integer division, the circuit allowed two outputs, only one of which was valid.  Additionally, the result of division by zero was underconstrained.\n\nThis vulnerability was identified using the Picus tool from Veridise. \n\nImpacted on-chain verifiers have already been disabled via the estop mechanism outlined in the [Verifier Management Design](https://github.com/risc0/risc0-ethereum/blob/release-2.0/contracts/version-management-design.md#base-verifier-implementations). \n\n## Mitigation\n\nWe recommend all impacted users upgrade as soon as possible.\n\nRust applications using the `risc0-zkvm` crate at versions \u003c 2.2 should upgrade to version 2.2.0 or later. \n\nSmart contract applications using the official [RISC Zero Verifier Router](https://dev.risczero.com/api/blockchain-integration/contracts/verifier#verifier-router) do not need to take any action: zkVM version 2.2 is active on all official routers, and version 2.1 has been disabled.\n\nSmart contract applications not using the verifier router should update their contracts to send verification calls to the 2.2 version of the verifier.","status":"published","published":"2025-08-05T17:42:06Z","modified":"2025-08-06T14:32:02Z","cvss":[{"version":"4.0","score":2.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"cwes":["CWE-369"],"updated_at":"2026-11-02T15:46:46.006631Z"}]}}