{"id":"CVE-2020-26030","details":"An issue was discovered in Zammad before 3.4.1. There is an authentication bypass in the SSO endpoint via a crafted header, when SSO is not configured. An attacker can create a valid and authenticated session that can be used to perform any actions in the name of other users.","modified":"2026-04-12T00:37:10.492306Z","published":"2020-12-28T08:15:11.257Z","references":[{"type":"ADVISORY","url":"https://zammad.com/news/security-advisory-zaa-2020-18"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/zammad/zammad","events":[{"introduced":"9bdf6d7b816d4e55501e13d12dc0d9b53cf16f5c"},{"fixed":"a12d45896b1518190fe00a120d6b92f8c29f1f54"}],"database_specific":{"extracted_events":[{"introduced":"1.0.0"},{"fixed":"3.4.1"}],"source":"CPE_FIELD","cpe":"cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:*"}}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2020-26030.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}