{"id":"CVE-2026-114114","title":"Vyper through 0.5.0b1 Literal Value Substitution via Multi-byte Characters","summary":"Vyper 0.1.0b1 before 0.1.0b12, 0.1.0b14, and 0.4.1 through 0.5.0b1 mix character-based line offsets with Python's UTF-8 byte col_offset values in vyper/ast/parse.py, so multi-byte characters shift the source slices used to reconstruct la…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N","cvssSource":"cna","cwe":["CWE-176"],"vendor":"vyperlang","product":"vyper","affected":["vyper >= 0.1.0b1 < 0.1.0b12","vyper >= 0.1.0b14 < 0.1.0b15","vyper >= 0.4.1 <= 0.5.0b1"],"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-28T16:16:34.586520Z"},"exploitAvailable":true,"published":"2026-10-21","updated":"2026-10-28","sourceUpdated":"2026-10-28T16:17:33.395Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-114114","references":[{"url":"https://github.com/vyperlang/vyper/security/advisories/GHSA-r3c7-7xwm-6vfw","label":"GitHub Security Advisory (GHSA-r3c7-7xwm-6vfw)"},{"url":"https://www.vulncheck.com/advisories/vyper-through-0.5-0b1-literal-value-substitution-via-multi-byte-characters","label":"VulnCheck Advisory: Vyper through 0.5.0b1 Literal Value Substitution via Multi-byte Characters"}],"tags":["cve.org","exploit-available"],"epss":0.0026,"epssPercentile":0.179,"ingestedAt":"2026-10-21T01:37:08.010Z","slug":"CVE-2026-114114","body":"## Overview\n\nVyper 0.1.0b1 before 0.1.0b12, 0.1.0b14, and 0.4.1 through 0.5.0b1 mix character-based line offsets with Python's UTF-8 byte col_offset values in vyper/ast/parse.py, so multi-byte characters shift the source slices used to reconstruct later numeric literals. An attacker contributing source with non-ASCII identifiers that NFKC-normalize to ASCII, or an invisible byte-order mark, can silently substitute addresses, integers or other constants in compiled code.\n\n## Affected\n\n- `vyper >= 0.1.0b1 < 0.1.0b12`\n- `vyper >= 0.1.0b14 < 0.1.0b15`\n- `vyper >= 0.4.1 <= 0.5.0b1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":230744,"id":"CVE-2026-114114","ts":1793207731848,"field":"exploit_available","old":"false","new":"true"}]}