{"id":"CVE-2026-114114","state":"PUBLISHED","title":"Vyper through 0.5.0b1 Literal Value Substitution via Multi-byte Characters","description":"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 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.","publishedAt":"2026-10-21T00:37:12.518Z","updatedAt":"2026-10-28T16:17:33.395Z","severity":{"score":6,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["vyperlang vyper"],"affected":[{"vendor":"vyperlang","product":"vyper","packageURL":"pkg:pypi/vyper","defaultStatus":"unaffected","versions":[{"version":"0.1.0b1","status":"affected","lessThan":"0.1.0b12","versionType":"python"},{"version":"0.1.0b12","status":"unaffected","versionType":"python"}]},{"vendor":"vyperlang","product":"vyper","packageURL":"pkg:pypi/vyper","defaultStatus":"unaffected","versions":[{"version":"0.1.0b14","status":"affected","lessThan":"0.1.0b15","versionType":"python"},{"version":"0.1.0b15","status":"unaffected","versionType":"python"}]},{"vendor":"vyperlang","product":"vyper","packageURL":"pkg:pypi/vyper","defaultStatus":"unaffected","versions":[{"version":"0.4.1","status":"affected","lessThanOrEqual":"0.5.0b1","versionType":"python"}]}],"references":["https://github.com/vyperlang/vyper/security/advisories/GHSA-r3c7-7xwm-6vfw","https://www.vulncheck.com/advisories/vyper-through-0.5-0b1-literal-value-substitution-via-multi-byte-characters"],"weaknesses":["CWE-176"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/114xxx/CVE-2026-114114.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-114114","state":"PUBLISHED","datePublished":"2026-10-21T00:37:12.518Z","dateUpdated":"2026-10-28T16:17:33.395Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-20T21:48:58.503Z"},"containers":{"cna":{"title":"Vyper through 0.5.0b1 Literal Value Substitution via Multi-byte Characters","descriptions":[{"lang":"en","value":"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 later numeric literals. 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