{"id":"DRUPAL-CONTRIB-2025-043","details":"Block Class enables you to add custom attributes to blocks.\n\nThe module did not sufficiently sanitize custom attribute input, allowing for potential XSS attacks when malicious JavaScript was injected as a custom attribute.\n\nThis vulnerability is mitigated by the fact that an attacker must have a role with the permission \"administer block classes\".","aliases":["CVE-2025-3902"],"modified":"2026-09-10T03:45:37.093409779Z","published":"2025-04-23T16:59:01Z","references":[{"type":"WEB","url":"https://www.drupal.org/sa-contrib-2025-043"}],"affected":[{"package":{"name":"drupal/block_class","ecosystem":"Packagist:https://packages.drupal.org/8","purl":"pkg:composer/drupal/block_class?repository_url=https:%2F%2Fpackages.drupal.org%2F8"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.0.1"}],"database_specific":{"constraint":"\u003e=4.0.0 \u003c4.0.1"}}],"database_specific":{"affected_versions":"\u003e=4.0.0 \u003c4.0.1","source":"https://github.com/DrupalSecurityTeam/drupal-advisory-database/blob/main/advisories/block_class/DRUPAL-CONTRIB-2025-043.json"}}],"schema_version":"1.9.0","credits":[{"name":"Ivo  Van Geertruyen (mr.baileys)","contact":["https://www.drupal.org/u/mrbaileys"]}]}