{"id":"CVE-2023-42460","aliases":["GHSA-cx2q-hfxr-rj97","PYSEC-2023-191"],"url":"https://o3.security/vulnerability/CVE-2023-42460","summary":"_abi_decode input not validated in complex expressions in Vyper","details":"Vyper is a Pythonic Smart Contract Language for the EVM. The `_abi_decode()` function does not validate input when it is nested in an expression. Uses of `_abi_decode()` can be constructed which allow for bounds checking to be bypassed resulting in incorrect results. This issue has not yet been fixed, but a fix is expected in release `0.3.10`. Users are advised to reference pull request #3626.","published":"2023-09-26T18:47:09.721Z","modified":"2026-08-12T03:51:14.381995335Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"PyPI","name":"vyper","fixedVersion":"0.3.10"}],"fix":{"url":"https://github.com/vyperlang/vyper/pull/3626","label":"vyperlang/vyper#3626"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/42xxx/CVE-2023-42460.json"},{"type":"ADVISORY","url":"https://github.com/vyperlang/vyper/security/advisories/GHSA-cx2q-hfxr-rj97"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-42460"},{"type":"FIX","url":"https://github.com/vyperlang/vyper/pull/3626"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:14.381995335Z"}}