{"id":"CVE-2025-46723","aliases":["GHSA-jf2r-x3j4-23m7"],"url":"https://o3.security/vulnerability/CVE-2025-46723","summary":"OpenVM byte decomposition of pc in AUIPC chip can overflow","details":"The fix to https://cantina.xyz/code/c486d600-bed0-4fc6-aed1-de759fd29fa2/findings/21 has a typo that still results in the highest limb of `pc` being range checked to 8-bits instead of 6-bits.\n\nIn the AIR, we do https://github.com/openvm-org/openvm/blob/0f94c8a3dfa7536c1231465d1bdee5fc607a5993/extensions/rv32im/circuit/src/auipc/core.rs#L135\n```\n        for (i, limb) in pc_limbs.iter().skip(1).enumerate() {\n            if i == pc_limbs.len() - 1 {\n```\n\nIt should be\n```\n        for (i, limb) in pc_limbs.iter().enumerate().skip(1) {\n```\n\nRight now the if statement is never triggered because the enumeration gives `i=0,1,2` when we instead want `i=1,2,3`. What this means is that `pc_limbs[3]` is range checked to 8-bits instead of 6-bits.\n\nThis leads to a vulnerability where the `pc_limbs` decomposition differs from the true `pc`, which means a malicious prover can make the destination register take a different value than the AUIPC instruction dictates, by making the decomposition overflow the BabyBear field.","published":"2025-05-02T22:18:55.696Z","modified":"2026-08-12T03:51:24.148623688Z","cvss":null,"epss":{"score":0.00455,"percentile":0.38073,"asOf":"2026-09-08"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"openvm","fixedVersion":"1.1.0"}],"fix":{"url":"https://github.com/openvm-org/openvm/commit/68da4b50c033da5603517064aa0a08e1bbf70a01","label":"openvm-org/openvm@68da4b5"},"references":[{"type":"WEB","url":"https://cantina.xyz/code/c486d600-bed0-4fc6-aed1-de759fd29fa2/findings/21"},{"type":"WEB","url":"https://github.com/openvm-org/openvm/blob/0f94c8a3dfa7536c1231465d1bdee5fc607a5993/extensions/rv32im/circuit/src/auipc/core.rs#L135"},{"type":"WEB","url":"https://github.com/openvm-org/openvm/releases/tag/v1.1.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46723.json"},{"type":"ADVISORY","url":"https://github.com/openvm-org/openvm/security/advisories/GHSA-jf2r-x3j4-23m7"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-46723"},{"type":"FIX","url":"https://github.com/openvm-org/openvm/commit/68da4b50c033da5603517064aa0a08e1bbf70a01"},{"type":"PACKAGE","url":"https://github.com/openvm-org/openvm"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:24.148623688Z"}}