{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.9.5"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3660bc00fd807deced3400a63bfa6db47811a3bb"
            }
          ],
          "repo": "https://github.com/open-webui/open-webui",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-3wgj-c2hg-vm6q"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-20"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56398.json"
  },
  "details": "Open WebUI before 0.9.5 contains a stored cross-site scripting vulnerability in the OAuth authentication flow where the picture claim URL MIME type is inferred from file extension rather than Content-Type header, allowing SVG files to bypass the profile image validator and be stored as data URIs. Authenticated users who visit the profile image endpoint receive attacker-controlled SVG content with inline disposition and no default security headers, enabling script execution in the same origin to steal authentication tokens and achieve account takeover.",
  "id": "CVE-2026-56398",
  "modified": "2026-07-17T03:41:42.843612112Z",
  "published": "2026-07-15T11:25:30.722Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56398.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-3wgj-c2hg-vm6q"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56398"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/open-webui-stored-cross-site-scripting-via-oauth-picture-claim-svg-data-uri"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Open WebUI - Stored Cross-Site Scripting via OAuth Picture Claim SVG Data URI"
}