{"id":"CVE-2021-27671","aliases":["GHSA-xmr7-v725-2jjr","RUSTSEC-2021-0026"],"url":"https://o3.security/vulnerability/CVE-2021-27671","summary":"Cross site scripting in comrak","details":"An issue was discovered in the comrak crate before 0.9.1 for Rust. Cross site scripting (XSS) can occur because the protection mechanism for data: and javascript: URIs is case-sensitive, allowing (for example) Data: to be used in an attack.","published":"2021-02-25T01:15:13.243Z","modified":"2026-07-09T01:30:32.991459Z","cvss":{"score":6.1,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},"epss":{"score":0.00686,"percentile":0.50712,"asOf":"2026-09-14"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"comrak","fixedVersion":"0.9.1"}],"fix":{"url":"https://github.com/kivikakk/comrak/commit/b3efbb6e427bcd33bb14db45753ad4fd98e0f5bf","label":"kivikakk/comrak@b3efbb6"},"references":[{"type":"ADVISORY","url":"https://rustsec.org/advisories/RUSTSEC-2021-0026.html"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-27671"},{"type":"WEB","url":"https://github.com/kivikakk/comrak/commit/b3efbb6e427bcd33bb14db45753ad4fd98e0f5bf"},{"type":"PACKAGE","url":"https://github.com/kivikakk/comrak"},{"type":"WEB","url":"https://github.com/kivikakk/comrak/releases/tag/0.9.1"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-09T01:30:32.991459Z"}}