{"id":"CVE-2026-44552","state":"PUBLISHED","title":"Open WebUI: Redis Cache Keys tool_servers and terminal_servers Missing Instance Prefix Enable Cross-Instance Cache Poisoning","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the tool_servers and terminal_servers keys in utils/tools.py do use a prefix. When two or more Open WebUI instances share a Redis database (a supported and documented deployment pattern, e.g., for multi-region deployments, blue-green setups, or cluster topologies), the unprefixed keys collide. An admin on Instance A writing to tool_servers overwrites the value read by Instance B — causing Instance B's users to receive Instance A's tool server configuration. This vulnerability is fixed in 0.9.0.","publishedAt":"2026-05-15T19:57:22.801Z","updatedAt":"2026-05-19T13:06:42.122Z","severity":{"score":8.7,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["open-webui open-webui"],"affected":[{"vendor":"open-webui","product":"open-webui","versions":[{"version":"< 0.9.0","status":"affected"}]}],"references":["https://github.com/open-webui/open-webui/security/advisories/GHSA-3x8w-4f7p-xxc2"],"weaknesses":["CWE-668"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/44xxx/CVE-2026-44552.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44552","state":"PUBLISHED","datePublished":"2026-05-15T19:57:22.801Z","dateUpdated":"2026-05-19T13:06:42.122Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-06T20:59:00.594Z"},"containers":{"cna":{"title":"Open WebUI: Redis Cache Keys tool_servers and terminal_servers Missing Instance Prefix Enable Cross-Instance Cache Poisoning","descriptions":[{"lang":"en","value":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the tool_servers and terminal_servers keys in utils/tools.py do use a prefix. When two or more Open WebUI instances share a Redis database (a supported and documented deployment pattern, e.g., for multi-region deployments, blue-green setups, or cluster topologies), the unprefixed keys collide. An admin on Instance A writing to tool_servers overwrites the value read by Instance B — causing Instance B's users to receive Instance A's tool server configuration. This vulnerability is fixed in 0.9.0."}],"affected":[{"vendor":"open-webui","product":"open-webui","versions":[{"version":"< 0.9.0","status":"affected"}]}],"references":[{"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3x8w-4f7p-xxc2","name":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3x8w-4f7p-xxc2","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-668","lang":"en","description":"CWE-668: Exposure of Resource to Wrong Sphere","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-15T19:57:22.801Z"},"source":{"advisory":"GHSA-3x8w-4f7p-xxc2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-19T03:55:41.079198Z","id":"CVE-2026-44552","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-19T13:06:42.122Z"}}]}}}