{"id":"CVE-2026-20896","summary":"Gitea Docker image trusts spoofable reverse-proxy headers by default","details":"Gitea Docker image versions up to and including 1.26.2 use REVERSE_PROXY_TRUSTED_PROXIES=* by default, allowing any source IP to impersonate a user when reverse-proxy authentication headers such as X-WEBAUTH-USER are enabled.","aliases":["GHSA-f75j-4cw6-rmx4","GO-2026-6051"],"modified":"2026-08-04T11:50:45.612711878Z","published":"2026-07-03T20:19:29.588Z","related":["openSUSE-SU-2026:21483-1"],"database_specific":{"cna_assigner":"Gitea","cwe_ids":["CWE-284"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/20xxx/CVE-2026-20896.json"},"references":[{"type":"ADVISORY","url":"https://blog.gitea.com/release-of-1.26.3-and-1.26.4/"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/20xxx/CVE-2026-20896.json"},{"type":"ADVISORY","url":"https://github.com/go-gitea/gitea/releases/tag/v1.26.3"},{"type":"ADVISORY","url":"https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20896"},{"type":"FIX","url":"https://github.com/go-gitea/gitea/pull/38151"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/go-gitea/gitea","events":[{"introduced":"0"},{"last_affected":"2c749ce548b1da0a52835861a87b888e67842d29"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"last_affected":"1.26.2"}]}}],"versions":["v1.26.2","v1.26.1","v1.26.0","v1.26.0-rc0","v1.27.0-dev","v1.26.0-dev","v1.25.0-dev","v1.24.0-dev","v1.22.0-rc1","v1.23.0-dev","v1.22.0-rc0","v1.21.0-rc0","v1.22.0-dev","v1.20.0-rc0","v1.21.0-dev","v1.20.0-dev","v1.19.0-rc0","v1.18.0-rc0","v1.19.0-dev","v1.18.0-dev","v1.17.0-dev","v1.16.0-rc1","v1.15.0-rc1","v1.16.0-dev","v1.15.0-dev","v1.14.0-dev","v1.13.0-dev","v1.12.0-dev","v1.10.5","v1.11.0-rc1","v1.10.0-rc1","v1.11.0-dev","v1.9.0-rc1","v1.10.0-dev","v1.9.0-dev","v1.7.0-dev","v1.6.0-rc1","v1.6.0-dev","v1.5.0-rc1","v1.5.0-dev","v1.1.0","v1.0.0","v0.9.99"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-20896.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}