{"id":"CVE-2026-44557","aliases":["EUVD-2026-30620","GHSA-6c2x-gcp3-gp73","PYSEC-2026-2707"],"status":"published","title":"Open WebUI: Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance. Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users. This vulnerability is fixed in 0.9.0.","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00221,"percentile":0.12773,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-200","CWE-862","CWE-863"],"published":"2026-05-08T19:51:33Z","modified":"2026-10-28T02:30:42Z","fixes":[{"ecosystem":"PyPI","package":"open-webui","fixed_in":["0.9.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.8.12"},{"fixed":"0.9.0"}]}]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.0"}]}],"versions":["0.1.124","0.1.125","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.3.1","0.3.10","0.3.12","0.3.13","0.3.14","0.3.15","0.3.16","0.3.17","0.3.17.dev2","0.3.17.dev3","0.3.17.dev4","0.3.17.dev5","0.3.18","0.3.19","0.3.2","0.3.20","0.3.21","0.3.22","0.3.23","0.3.24","0.3.25","0.3.26","0.3.27","0.3.27.dev1","0.3.27.dev2","0.3.27.dev3","0.3.28","0.3.29","0.3.3","0.3.30","0.3.30.dev1","0.3.30.dev2","0.3.31","0.3.31.dev1","0.3.32","0.3.33","0.3.33.dev1","0.3.34","0.3.35","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9","0.4.0","0.4.0.dev1","0.4.0.dev2","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5","0.4.6","0.4.6.dev1","0.4.7","0.4.8","0.5.0","0.5.0.dev1","0.5.0.dev2","0.5.1","0.5.10","0.5.11","0.5.12","0.5.13","0.5.14","0.5.15","0.5.16","0.5.17","0.5.18","0.5.19","0.5.2","0.5.20","0.5.3","0.5.3.dev1","0.5.4","0.5.5","0.5.6","0.5.7","0.5.8","0.5.9","0.6.0","0.6.1","0.6.10","0.6.11","0.6.12","0.6.13","0.6.14","0.6.15","0.6.16","0.6.18","0.6.19","0.6.2","0.6.20","0.6.21","0.6.22","0.6.23","0.6.24","0.6.25","0.6.26","0.6.26.dev1","0.6.27","0.6.28","0.6.29","0.6.3","0.6.30","0.6.31","0.6.32","0.6.33","0.6.34","0.6.35","0.6.36","0.6.37","0.6.38","0.6.39","0.6.4","0.6.40","0.6.41","0.6.42","0.6.43","0.6.5","0.6.6","0.6.6.dev1","0.6.7","0.6.8","0.6.9","0.7.0","0.7.1","0.7.2","0.8.0","0.8.1","0.8.10","0.8.11","0.8.12","0.8.2","0.8.3","0.8.4","0.8.5","0.8.6","0.8.7","0.8.8","0.8.9"]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.0"}]}],"versions":["0.1.124","0.1.125","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.3.1","0.3.10","0.3.12","0.3.13","0.3.14","0.3.15","0.3.16","0.3.17","0.3.17.dev2","0.3.17.dev3","0.3.17.dev4","0.3.17.dev5","0.3.18","0.3.19","0.3.2","0.3.20","0.3.21","0.3.22","0.3.23","0.3.24","0.3.25","0.3.26","0.3.27","0.3.27.dev1","0.3.27.dev2","0.3.27.dev3","0.3.28","0.3.29","0.3.3","0.3.30","0.3.30.dev1","0.3.30.dev2","0.3.31","0.3.31.dev1","0.3.32","0.3.33","0.3.33.dev1","0.3.34","0.3.35","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9","0.4.0","0.4.0.dev1","0.4.0.dev2","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5","0.4.6","0.4.6.dev1","0.4.7","0.4.8","0.5.0","0.5.0.dev1","0.5.0.dev2","0.5.1","0.5.10","0.5.11","0.5.12","0.5.13","0.5.14","0.5.15","0.5.16","0.5.17","0.5.18","0.5.19","0.5.2","0.5.20","0.5.3","0.5.3.dev1","0.5.4","0.5.5","0.5.6","0.5.7","0.5.8","0.5.9","0.6.0","0.6.1","0.6.10","0.6.11","0.6.12","0.6.13","0.6.14","0.6.15","0.6.16","0.6.18","0.6.19","0.6.2","0.6.20","0.6.21","0.6.22","0.6.23","0.6.24","0.6.25","0.6.26","0.6.26.dev1","0.6.27","0.6.28","0.6.29","0.6.3","0.6.30","0.6.31","0.6.32","0.6.33","0.6.34","0.6.35","0.6.36","0.6.37","0.6.38","0.6.39","0.6.4","0.6.40","0.6.41","0.6.42","0.6.43","0.6.5","0.6.6","0.6.6.dev1","0.6.7","0.6.8","0.6.9","0.7.0","0.7.1","0.7.2","0.8.0","0.8.1","0.8.10","0.8.11","0.8.12","0.8.2","0.8.3","0.8.4","0.8.5","0.8.6","0.8.7","0.8.8","0.8.9"]}],"products":[{"vendor":"open-webui","product":"open-webui"},{"vendor":"openwebui","product":"open_webui"}],"references":[{"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-6c2x-gcp3-gp73","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44557","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-6c2x-gcp3-gp73","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44557.json","tags":["advisory"]},{"url":"https://github.com/open-webui/open-webui","tags":["package"]},{"url":"https://pypi.org/project/open-webui","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-44557","title":"Open WebUI: Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance. Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users. This vulnerability is fixed in 0.9.0.","status":"published","published":"2026-05-15T19:44:49.651Z","modified":"2026-05-18T14:32:50.052Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T13:43:00.288193Z"}],"euvd":[{"id":"EUVD-2026-30620","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance. Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users. This vulnerability is fixed in 0.9.0.","status":"published","published":"2026-05-15T19:44:49Z","modified":"2026-05-18T14:32:50Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T18:21:16.642345Z"}],"ghsa":[{"id":"GHSA-6c2x-gcp3-gp73","title":"Open WebUI vulnerable to Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"# Global Knowledge Base Enumeration via knowledge-bases Meta-Collection\n\n## Affected Component\n\nRetrieval collection access validation:\n- `backend/open_webui/routers/retrieval.py` (lines 2330-2355, `_validate_collection_access`)\n- `backend/open_webui/routers/retrieval.py` (query endpoints, e.g. `POST /query/doc`)\n\n## Affected Versions\n\nCurrent main branch (commit `6fdd19bf1`) and likely all versions with the knowledge base subsystem.\n\n## Description\n\nThe `_validate_collection_access` function uses an incomplete allowlist that only enforces ownership checks for collections matching `user-memory-*` and `file-*` patterns. All other collection names pass through unchecked — including the system-level `knowledge-bases` meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance.\n\nAny authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users.\n\n```python\n# retrieval.py:2330-2355 — incomplete collection allowlist\ndef _validate_collection_access(user, collection_name, ...):\n    if collection_name.startswith('user-memory-'):\n        # Check user-memory ownership\n        ...\n    elif collection_name.startswith('file-'):\n        # Check file access\n        ...\n    # Everything else (including \"knowledge-bases\") passes through unchecked\n```\n\nThis finding is the enabler for the KB destruction (`process/web`), KB content injection (`process/file`), and RAG vector search access bypass findings — all of which require knowing a target KB's UUID. Without this enumeration, UUIDs are random and practically unguessable; with it, UUIDs across the entire instance are trivially obtained.\n\n## CVSS 3.1 Breakdown\n\n| Metric | Value | Rationale |\n|--------|-------|-----------|\n| Attack Vector | Network (N) | Exploited remotely via API call |\n| Attack Complexity | Low (L) | Single API call |\n| Privileges Required | Low (L) | Requires any authenticated user account |\n| User Interaction | None (N) | No victim interaction required |\n| Scope | Unchanged (U) | Impact within the knowledge base boundary |\n| Confidentiality | Low (L) | Discloses KB metadata (IDs, names, descriptions) across all users |\n| Integrity | None (N) | No direct data modification |\n| Availability | None (N) | No denial of service |\n\n## Attack Scenario\n\n1. Attacker (any authenticated user) sends:\n   ```\n   POST /api/v1/retrieval/query/doc\n   {\n     \"collection_name\": \"knowledge-bases\",\n     \"query\": \"confidential\"\n   }\n   ```\n2. `_validate_collection_access` does not recognize the `knowledge-bases` prefix and lets the request pass.\n3. The vector search returns the most relevant documents from the meta-collection — knowledge base records including their UUIDs, names, and descriptions — across all users on the instance.\n4. Attacker varies the query to enumerate more KBs: `\"project\"`, `\"internal\"`, `\"private\"`, etc.\n5. Attacker now has a full target list for subsequent attacks (destruction, poisoning, content extraction).\n\n## Impact\n\n- **Information disclosure:** KB names and descriptions may reveal sensitive project names, internal initiatives, or user activities\n- **Enabler for other attacks:** Unlocks the following findings by supplying the required target UUIDs:\n  - KB destruction/poisoning via `process/web`\n  - Cross-user content injection via `process/file`\n  - RAG vector search access bypass in `retrieval/utils.py`\n- Transforms these from theoretical (requires UUID guessing) to trivially exploitable (UUIDs enumerable)\n\n## Preconditions\n\n- Attacker must have a valid user account","status":"published","published":"2026-05-08T19:51:33Z","modified":"2026-05-15T23:53:00Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-200","CWE-862","CWE-863"],"updated_at":"2026-11-02T14:40:11.298154Z"}],"nvd":[{"id":"CVE-2026-44557","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance. Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users. This vulnerability is fixed in 0.9.0.","status":"published","published":"2026-05-15T20:16:47.227Z","modified":"2026-06-17T10:50:47.33Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T14:12:19.39893Z"}],"osv":[{"id":"CVE-2026-44557","title":"Open WebUI: Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance. Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users. This vulnerability is fixed in 0.9.0.","status":"published","published":"2026-05-15T19:44:49.651Z","modified":"2026-10-28T02:30:42.920026597Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T15:45:05.172514Z"},{"id":"GHSA-6c2x-gcp3-gp73","title":"Open WebUI vulnerable to Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"# Global Knowledge Base Enumeration via knowledge-bases Meta-Collection\n\n## Affected Component\n\nRetrieval collection access validation:\n- `backend/open_webui/routers/retrieval.py` (lines 2330-2355, `_validate_collection_access`)\n- `backend/open_webui/routers/retrieval.py` (query endpoints, e.g. `POST /query/doc`)\n\n## Affected Versions\n\nCurrent main branch (commit `6fdd19bf1`) and likely all versions with the knowledge base subsystem.\n\n## Description\n\nThe `_validate_collection_access` function uses an incomplete allowlist that only enforces ownership checks for collections matching `user-memory-*` and `file-*` patterns. All other collection names pass through unchecked — including the system-level `knowledge-bases` meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance.\n\nAny authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users.\n\n```python\n# retrieval.py:2330-2355 — incomplete collection allowlist\ndef _validate_collection_access(user, collection_name, ...):\n    if collection_name.startswith('user-memory-'):\n        # Check user-memory ownership\n        ...\n    elif collection_name.startswith('file-'):\n        # Check file access\n        ...\n    # Everything else (including \"knowledge-bases\") passes through unchecked\n```\n\nThis finding is the enabler for the KB destruction (`process/web`), KB content injection (`process/file`), and RAG vector search access bypass findings — all of which require knowing a target KB's UUID. Without this enumeration, UUIDs are random and practically unguessable; with it, UUIDs across the entire instance are trivially obtained.\n\n## CVSS 3.1 Breakdown\n\n| Metric | Value | Rationale |\n|--------|-------|-----------|\n| Attack Vector | Network (N) | Exploited remotely via API call |\n| Attack Complexity | Low (L) | Single API call |\n| Privileges Required | Low (L) | Requires any authenticated user account |\n| User Interaction | None (N) | No victim interaction required |\n| Scope | Unchanged (U) | Impact within the knowledge base boundary |\n| Confidentiality | Low (L) | Discloses KB metadata (IDs, names, descriptions) across all users |\n| Integrity | None (N) | No direct data modification |\n| Availability | None (N) | No denial of service |\n\n## Attack Scenario\n\n1. Attacker (any authenticated user) sends:\n   ```\n   POST /api/v1/retrieval/query/doc\n   {\n     \"collection_name\": \"knowledge-bases\",\n     \"query\": \"confidential\"\n   }\n   ```\n2. `_validate_collection_access` does not recognize the `knowledge-bases` prefix and lets the request pass.\n3. The vector search returns the most relevant documents from the meta-collection — knowledge base records including their UUIDs, names, and descriptions — across all users on the instance.\n4. Attacker varies the query to enumerate more KBs: `\"project\"`, `\"internal\"`, `\"private\"`, etc.\n5. Attacker now has a full target list for subsequent attacks (destruction, poisoning, content extraction).\n\n## Impact\n\n- **Information disclosure:** KB names and descriptions may reveal sensitive project names, internal initiatives, or user activities\n- **Enabler for other attacks:** Unlocks the following findings by supplying the required target UUIDs:\n  - KB destruction/poisoning via `process/web`\n  - Cross-user content injection via `process/file`\n  - RAG vector search access bypass in `retrieval/utils.py`\n- Transforms these from theoretical (requires UUID guessing) to trivially exploitable (UUIDs enumerable)\n\n## Preconditions\n\n- Attacker must have a valid user account","status":"published","published":"2026-05-08T19:51:33Z","modified":"2026-07-13T16:43:33.016553138Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-200","CWE-862","CWE-863"],"updated_at":"2026-11-02T15:46:39.618611Z"},{"id":"PYSEC-2026-2707","title":"Open WebUI vulnerable to Global Knowledge Base Enumeration via knowledge-bases Meta-Collection","description":"# Global Knowledge Base Enumeration via knowledge-bases Meta-Collection\n\n## Affected Component\n\nRetrieval collection access validation:\n- `backend/open_webui/routers/retrieval.py` (lines 2330-2355, `_validate_collection_access`)\n- `backend/open_webui/routers/retrieval.py` (query endpoints, e.g. `POST /query/doc`)\n\n## Affected Versions\n\nCurrent main branch (commit `6fdd19bf1`) and likely all versions with the knowledge base subsystem.\n\n## Description\n\nThe `_validate_collection_access` function uses an incomplete allowlist that only enforces ownership checks for collections matching `user-memory-*` and `file-*` patterns. All other collection names pass through unchecked — including the system-level `knowledge-bases` meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance.\n\nAny authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users.\n\n```python\n# retrieval.py:2330-2355 — incomplete collection allowlist\ndef _validate_collection_access(user, collection_name, ...):\n    if collection_name.startswith('user-memory-'):\n        # Check user-memory ownership\n        ...\n    elif collection_name.startswith('file-'):\n        # Check file access\n        ...\n    # Everything else (including \"knowledge-bases\") passes through unchecked\n```\n\nThis finding is the enabler for the KB destruction (`process/web`), KB content injection (`process/file`), and RAG vector search access bypass findings — all of which require knowing a target KB's UUID. Without this enumeration, UUIDs are random and practically unguessable; with it, UUIDs across the entire instance are trivially obtained.\n\n## CVSS 3.1 Breakdown\n\n| Metric | Value | Rationale |\n|--------|-------|-----------|\n| Attack Vector | Network (N) | Exploited remotely via API call |\n| Attack Complexity | Low (L) | Single API call |\n| Privileges Required | Low (L) | Requires any authenticated user account |\n| User Interaction | None (N) | No victim interaction required |\n| Scope | Unchanged (U) | Impact within the knowledge base boundary |\n| Confidentiality | Low (L) | Discloses KB metadata (IDs, names, descriptions) across all users |\n| Integrity | None (N) | No direct data modification |\n| Availability | None (N) | No denial of service |\n\n## Attack Scenario\n\n1. Attacker (any authenticated user) sends:\n   ```\n   POST /api/v1/retrieval/query/doc\n   {\n     \"collection_name\": \"knowledge-bases\",\n     \"query\": \"confidential\"\n   }\n   ```\n2. `_validate_collection_access` does not recognize the `knowledge-bases` prefix and lets the request pass.\n3. The vector search returns the most relevant documents from the meta-collection — knowledge base records including their UUIDs, names, and descriptions — across all users on the instance.\n4. Attacker varies the query to enumerate more KBs: `\"project\"`, `\"internal\"`, `\"private\"`, etc.\n5. Attacker now has a full target list for subsequent attacks (destruction, poisoning, content extraction).\n\n## Impact\n\n- **Information disclosure:** KB names and descriptions may reveal sensitive project names, internal initiatives, or user activities\n- **Enabler for other attacks:** Unlocks the following findings by supplying the required target UUIDs:\n  - KB destruction/poisoning via `process/web`\n  - Cross-user content injection via `process/file`\n  - RAG vector search access bypass in `retrieval/utils.py`\n- Transforms these from theoretical (requires UUID guessing) to trivially exploitable (UUIDs enumerable)\n\n## Preconditions\n\n- Attacker must have a valid user account","status":"published","published":"2026-07-13T15:15:42.174376Z","modified":"2026-07-13T16:32:17.829468253Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:55.961245Z"}]}}