{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-87994", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-09-09T19:19:27.405Z", "datePublished": "2026-09-09T21:24:55.896Z", "dateUpdated": "2026-09-10T15:59:55.721Z"}, "containers": {"cna": {"title": "Open WebUI: Channel members can overwrite another member's message via the chat completions endpoint", "problemTypes": [{"descriptions": [{"cweId": "CWE-639", "lang": "en", "description": "CWE-639: Authorization Bypass Through User-Controlled Key", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-862", "lang": "en", "description": "CWE-862: Missing Authorization", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8"}, {"name": "https://github.com/open-webui/open-webui/pull/28631", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-webui/open-webui/pull/28631"}, {"name": "https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc"}, {"name": "https://github.com/open-webui/open-webui/releases/tag/v0.11.1", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-webui/open-webui/releases/tag/v0.11.1"}], "affected": [{"vendor": "open-webui", "product": "open-webui", "versions": [{"version": ">= 0.9.5, < 0.11.1", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-09T21:24:55.896Z"}, "descriptions": [{"lang": "en", "value": "Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1."}], "source": {"advisory": "GHSA-fmqh-xp37-5hr8", "discovery": "UNKNOWN"}}, "adp": [{"references": [{"url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-10T15:59:49.963213Z", "id": "CVE-2026-87994", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-10T15:59:55.721Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"cna": {"title": "Open WebUI: Channel members can overwrite another member's message via the chat completions endpoint", "source": {"advisory": "GHSA-fmqh-xp37-5hr8", "discovery": "UNKNOWN"}, "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}], "affected": [{"vendor": "open-webui", "product": "open-webui", "versions": [{"status": "affected", "version": ">= 0.9.5, < 0.11.1"}]}], "references": [{"url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8", "name": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8", "tags": ["x_refsource_CONFIRM"]}, {"url": "https://github.com/open-webui/open-webui/pull/28631", "name": "https://github.com/open-webui/open-webui/pull/28631", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc", "name": "https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/open-webui/open-webui/releases/tag/v0.11.1", "name": "https://github.com/open-webui/open-webui/releases/tag/v0.11.1", "tags": ["x_refsource_MISC"]}], "descriptions": [{"lang": "en", "value": "Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-639", "description": "CWE-639: Authorization Bypass Through User-Controlled Key"}]}, {"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-862", "description": "CWE-862: Missing Authorization"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-09T21:24:55.896Z"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-87994", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-10T15:59:49.963213Z"}}}], "references": [{"url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8", "tags": ["exploit"]}], "providerMetadata": {"shortName": "CISA-ADP", "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "dateUpdated": "2026-09-10T15:59:33.603Z"}}]}, "cveMetadata": {"cveId": "CVE-2026-87994", "state": "PUBLISHED", "dateUpdated": "2026-09-09T21:24:55.896Z", "dateReserved": "2026-09-09T19:19:27.405Z", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "datePublished": "2026-09-09T21:24:55.896Z", "assignerShortName": "GitHub_M"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"product": "open-webui", "vendor": "open-webui", "versions": [{"status": "affected", "version": ">= 0.9.5, < 0.11.1"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1."}], "id": "CVE-2026-87994", "lastModified": "2026-09-10T16:18:07.320", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "[email protected]", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-87994", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-10T15:59:49.963213Z", "version": "2.0.3"}}]}, "published": "2026-09-09T22:18:47.563", "references": [{"source": "[email protected]", "url": "https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc"}, {"source": "[email protected]", "url": "https://github.com/open-webui/open-webui/pull/28631"}, {"source": "[email protected]", "url": "https://github.com/open-webui/open-webui/releases/tag/v0.11.1"}, {"source": "[email protected]", "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-639"}, {"lang": "en", "value": "CWE-862"}], "source": "[email protected]", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0.9.5,0.11.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "open-webui", "source": "cna", "vendor": "open-webui"}, "product": "open-webui", "vendor": "open-webui"}], "created": "2026-09-09T23:15:17.621949+00:00", "updated": "2026-09-10T11:30:06.678020+00:00", "vendors": ["open-webui", "open-webui$PRODUCT$open-webui"]}