{"id":"CVE-2021-48012","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-48012","generatedAt":"2026-10-27T21:45:58.431Z","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.","description":"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 [constructor.prototype] table headers or __proto__.x dotted keys to parse() to pollute all objects, causing denial of service or authorization bypass.","published":"2026-10-12T21:17:06.000Z","lastModified":"2026-10-26T18:17:04.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":8.8,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-1321"],"affected":[],"epss":{"score":0.00414,"percentile":0.35491,"date":"2026-10-26","history":[{"date":"2026-10-13","score":0.00414,"percentile":0.33961}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.41%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-12T21:17:06.000Z","detail":{"score":"8.8","severity":"HIGH","publishedAt":"2026-10-12T21:17:06.057Z"},"summary":"New CVE, high severity (CVSS 8.8)."}],"references":[{"url":"https://github.com/Gin-Quin/fast-toml","source":"disclosure@vulncheck.com"},{"url":"https://github.com/Gin-Quin/fast-toml/issues/8","source":"disclosure@vulncheck.com"},{"url":"https://github.com/Gin-Quin/fast-toml/pull/3","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/fast-toml-through-0.5.4-prototype-pollution-via-proto-keys-in-parsed-toml","source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-48012","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}