Description

OpenVM is a performant and modular zkVM framework built for customization and extensibility. In version 1.0.0, OpenVM is vulnerable to overflow through byte decomposition of pc in AUIPC chip. A typo results in the highest limb of pc being range checked to 8-bits instead of 6-bits. This results in the if statement never being triggered because the enumeration gives i=0,1,2, when instead the enumeration should give i=1,2,3, leaving pc_limbs[3] range checked to 8-bits instead of 6-bits. This 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. This issue has been patched in version 1.1.0.

Classification

CVE ID: CVE-2025-46723

CVSS Base Severity: HIGH

CVSS Base Score: 7.8

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

Affected Products

Vendor: openvm-org

Product: openvm

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.06% (probability of being exploited)

EPSS Percentile: 18.88% (scored less or equal to compared to others)

EPSS Date: 2025-05-31 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-46723
https://github.com/openvm-org/openvm/security/advisories/GHSA-jf2r-x3j4-23m7
https://github.com/openvm-org/openvm/commit/68da4b50c033da5603517064aa0a08e1bbf70a01
https://cantina.xyz/code/c486d600-bed0-4fc6-aed1-de759fd29fa2/findings/21
https://github.com/openvm-org/openvm/blob/0f94c8a3dfa7536c1231465d1bdee5fc607a5993/extensions/rv32im/circuit/src/auipc/core.rs#L135
https://github.com/openvm-org/openvm/releases/tag/v1.1.0

Timeline