Security advisory

{
  "id": "ebda9da3801aa706fb67de073ec6f5552b2c9c549f83eeedf0e793d0fca55c62",
  "url": "https://osv.dev/vulnerability/CVE-2020-26030",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-26030",
    "summary": "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.",
    "evidence": "osv:CVE-2020-26030",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2020-26030",
      "aliases": [
        "CVE-2020-26030"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/zammad/zammad",
              "type": "GIT",
              "events": [
                {
                  "introduced": "9bdf6d7b816d4e55501e13d12dc0d9b53cf16f5c"
                },
                {
                  "fixed": "a12d45896b1518190fe00a120d6b92f8c29f1f54"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "fixed": "3.4.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-26030.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:24.446115125Z",
      "provider": "osv",
      "references": [
        "https://zammad.com/news/security-advisory-zaa-2020-18"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-26030",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 431155,
  "published_at": "2020-12-28T08:15:11.257+00:00"
}