{"id":"CVE-2026-86433","revision":"4d4134ef556e4fa8be59c9d1831f09d9","records":[{"revision":"4d4134ef556e4fa8be59c9d1831f09d9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-86433","aliases":[],"title":"commonmark 1.5.0 before 2.8.4 Denial of Service via Attributes","description":"commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection() performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks to cause parsing to take over 5 seconds, exhausting server resources.","state":0,"publishedAt":"2026-09-07T12:53:52.562+00:00","modifiedAt":"2026-10-08T15:25:53.98+00:00","affected":[{"ecosystem":"Vendor product","name":"commonmark","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"thephpleague\",\n                    \"product\": \"commonmark\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"versions\": [\n                        {\n                            \"version\": \"1.5.0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\",\n                            \"lessThan\": \"2.8.4\"\n                        },\n                        {\n                            \"version\": \"2.8.4\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"packageURL\": \"pkg:composer/league/commonmark\"\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.7,"severity":"HIGH"},{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/thephpleague/commonmark/security/advisories/GHSA-g2gp-3wwq-f4ph","https://www.vulncheck.com/advisories/commonmark-1.5.0-before-2.8.4-denial-of-service-via-attributes"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-86433","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-86433","identifiers":["CVE-2026-86433"]},"retained":false,"historicalAffected":[]}],"coverage":[]}