{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Gitea Open Source Git Server",
          "vendor": "Gitea",
          "versions": [
            {
              "lessThanOrEqual": "1.26.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "rz1027"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "CWE-284",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-03T20:19:29.588Z",
        "orgId": "88ee5874-cf24-4952-aea0-31affedb7ff2",
        "shortName": "Gitea"
      },
      "references": [
        {
          "name": "GitHub Security Advisory",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://github.com/go-gitea/gitea/security/advisories/GHSA-f75j-4cw6-rmx4"
        },
        {
          "name": "GitHub Pull Request #38151",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/go-gitea/gitea/pull/38151"
        },
        {
          "name": "Gitea v1.26.3 Release",
          "tags": [
            "release-notes"
          ],
          "url": "https://github.com/go-gitea/gitea/releases/tag/v1.26.3"
        },
        {
          "name": "Gitea v1.26.4 Release Blog Post",
          "tags": [
            "release-notes"
          ],
          "url": "https://blog.gitea.com/release-of-1.26.3-and-1.26.4/"
        }
      ],
      "title": "Gitea Docker image trusts spoofable reverse-proxy headers by default",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "88ee5874-cf24-4952-aea0-31affedb7ff2",
    "assignerShortName": "Gitea",
    "cveId": "CVE-2026-20896",
    "datePublished": "2026-07-03T20:19:29.588Z",
    "dateReserved": "2026-03-03T03:25:59.988Z",
    "dateUpdated": "2026-07-03T20:19:29.588Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}