{"id":"CVE-2021-48012","title":"fast-toml through 0.5.4 contains a prototype pollution vulnerability that allows attackers to modify Object.prototype by supplying TOML containing __proto__, constructor or prototype key segments","summary":"fast-toml through 0.5.4 contains a prototype pollution vulnerability that allows attackers to modify Object.prototype by supplying TOML containing __proto__, constructor or prototype key segments. Attackers can pass [__proto__] or [const…","severity":"high","cvss":8.2,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L","cwe":["CWE-1321"],"published":"2026-10-12","updated":"2026-10-12","sourceUpdated":"2026-10-12T21:17:06.057","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-48012","references":[{"url":"https://github.com/Gin-Quin/fast-toml","label":"disclosure@vulncheck.com"},{"url":"https://github.com/Gin-Quin/fast-toml/issues/8","label":"disclosure@vulncheck.com"},{"url":"https://github.com/Gin-Quin/fast-toml/pull/3","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/fast-toml-through-0.5.4-prototype-pollution-via-proto-keys-in-parsed-toml","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"ingestedAt":"2026-10-12T22:05:40.350Z","slug":"CVE-2021-48012","body":"## Overview\n\nfast-toml through 0.5.4 contains a prototype pollution vulnerability that allows attackers to modify Object.prototype by supplying TOML containing __proto__, constructor or prototype key segments. Attackers can pass [__proto__] or [constructor.prototype] table headers or __proto__.x dotted keys to parse() to pollute all objects, causing denial of service or authorization bypass.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":45.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}