{"id":"CVE-2021-21236","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-21236","generatedAt":"2026-10-27T22:27:25.969Z","title":"In CairoSVG before version 2.5.1, there is a regular expression denial of service (REDoS) vulnerability.","description":"CairoSVG is a Python (pypi) package. CairoSVG is an SVG converter based on Cairo. In CairoSVG before version 2.5.1, there is a regular expression denial of service (REDoS) vulnerability. When processing SVG files, the python package CairoSVG uses two regular expressions which are vulnerable to Regular Expression Denial of Service (REDoS). If an attacker provides a malicious SVG, it can make cairosvg get stuck processing the file for a very long time. This is fixed in version 2.5.1. See Referenced GitHub advisory for more information.","published":"2021-01-06T17:15:24.000Z","lastModified":"2026-06-17T03:35:06.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},"cwe":["CWE-400"],"affected":["courtbouillon/cairosvg"],"epss":{"score":0.01368,"percentile":0.71683,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (1.37%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/Kozea/CairoSVG/commit/cfc9175e590531d90384aa88845052de53d94bf3","tags":["Patch","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/Kozea/CairoSVG/releases/tag/2.5.1","tags":["Release Notes","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/Kozea/CairoSVG/security/advisories/GHSA-hq37-853p-g5cf","tags":["Exploit","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://pypi.org/project/CairoSVG/","tags":["Product","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/Kozea/CairoSVG/commit/cfc9175e590531d90384aa88845052de53d94bf3","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/Kozea/CairoSVG/releases/tag/2.5.1","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/Kozea/CairoSVG/security/advisories/GHSA-hq37-853p-g5cf","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://pypi.org/project/CairoSVG/","tags":["Product","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-21236","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."}