{"id":"CVE-2018-20583","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-20583","generatedAt":"2026-10-28T20:11:00.244Z","title":"Cross-site scripting (XSS) vulnerability in the PHP League CommonMark library versions 0.15.6 through 0.18.x before 0.18.1 allows remote attackers to insert unsafe URLs into HTML (even if allow_unsafe_links is false) via a newline character (e.g.,…","description":"Cross-site scripting (XSS) vulnerability in the PHP League CommonMark library versions 0.15.6 through 0.18.x before 0.18.1 allows remote attackers to insert unsafe URLs into HTML (even if allow_unsafe_links is false) via a newline character (e.g., writing javascript as javascri%0apt).","published":"2018-12-30T05:29:01.000Z","lastModified":"2026-06-17T01:53:08.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":6.1,"severity":"MEDIUM","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},"cwe":["CWE-79"],"affected":["thephpleague/commonmark"],"epss":{"score":0.01863,"percentile":0.79152,"date":"2026-10-27","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 (1.86%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://commonmark.thephpleague.com/changelog/","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/thephpleague/commonmark/issues/337","tags":["Exploit","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/thephpleague/commonmark/releases/tag/0.18.1","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://commonmark.thephpleague.com/changelog/","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/thephpleague/commonmark/issues/337","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/thephpleague/commonmark/releases/tag/0.18.1","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-20583","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."}