{"api_version":"1","generated_at":"2026-05-16T01:42:49+00:00","cve":"CVE-2026-45315","urls":{"html":"https://cve.report/CVE-2026-45315","api":"https://cve.report/api/cve/CVE-2026-45315.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-45315","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-45315"},"summary":{"title":"Open WebUI: Stored XSS via attacker-controlled file extension in /api/v1/audio/transcriptions","description":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the audio transcription upload endpoint takes the file extension from the user-supplied filename and saves the file under CACHE_DIR/audio/transcriptions/.. The /cache/{path} route serves these files via FileResponse, which sets Content-Type from the on-disk extension and emits no Content-Disposition. A verified user with the default-on chat.stt permission can upload a polyglot WAV+HTML file named pwn.html and trick any other user into opening the resulting URL — the response comes back as text/html and any embedded <script> runs in the Open WebUI origin. This vulnerability is fixed in 0.9.3.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-05-15 22:16:54","updated_at":"2026-05-15 22:16:54"},"problem_types":["CWE-79","CWE-434","CWE-646","CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","CWE-434 CWE-434: Unrestricted Upload of File with Dangerous Type","CWE-646 CWE-646: Reliance on File Name or Extension of Externally-Supplied File"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"8.7","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","baseScore":8.7,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.7","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","version":"3.1"}}],"references":[{"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr","name":"https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-45315","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45315","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"open-webui","product":"open-webui","version":"affected < 0.9.3","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"open-webui","vendor":"open-webui","versions":[{"status":"affected","version":"< 0.9.3"}]}],"descriptions":[{"lang":"en","value":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the audio transcription upload endpoint takes the file extension from the user-supplied filename and saves the file under CACHE_DIR/audio/transcriptions/.. The /cache/{path} route serves these files via FileResponse, which sets Content-Type from the on-disk extension and emits no Content-Disposition. A verified user with the default-on chat.stt permission can upload a polyglot WAV+HTML file named pwn.html and trick any other user into opening the resulting URL — the response comes back as text/html and any embedded <script> runs in the Open WebUI origin. This vulnerability is fixed in 0.9.3."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-434","description":"CWE-434: Unrestricted Upload of File with Dangerous Type","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-646","description":"CWE-646: Reliance on File Name or Extension of Externally-Supplied File","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-05-15T21:26:54.790Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr","tags":["x_refsource_CONFIRM"],"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-m8f9-9whg-f4xr"}],"source":{"advisory":"GHSA-m8f9-9whg-f4xr","discovery":"UNKNOWN"},"title":"Open WebUI: Stored XSS via attacker-controlled file extension in /api/v1/audio/transcriptions"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-45315","datePublished":"2026-05-15T21:26:54.790Z","dateReserved":"2026-05-11T20:50:30.538Z","dateUpdated":"2026-05-15T21:26:54.790Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-15 22:16:54","lastModifiedDate":"2026-05-15 22:16:54","problem_types":["CWE-79","CWE-434","CWE-646","CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","CWE-434 CWE-434: Unrestricted Upload of File with Dangerous Type","CWE-646 CWE-646: Reliance on File Name or Extension of Externally-Supplied File"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","baseScore":8.7,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":2.3,"impactScore":5.8}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"45315","Ordinal":"1","Title":"Open WebUI: Stored XSS via attacker-controlled file extension in","CVE":"CVE-2026-45315","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"45315","Ordinal":"1","NoteData":"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the audio transcription upload endpoint takes the file extension from the user-supplied filename and saves the file under CACHE_DIR/audio/transcriptions/.. The /cache/{path} route serves these files via FileResponse, which sets Content-Type from the on-disk extension and emits no Content-Disposition. A verified user with the default-on chat.stt permission can upload a polyglot WAV+HTML file named pwn.html and trick any other user into opening the resulting URL — the response comes back as text/html and any embedded <script> runs in the Open WebUI origin. This vulnerability is fixed in 0.9.3.","Type":"Description","Title":"Open WebUI: Stored XSS via attacker-controlled file extension in"}]}}}