{"cve":"CVE-2026-56398","nvd":{"published":"2026-07-15T12:18:02.870","modified":"2026-07-16T20:03:37.680","status":"Analyzed","description":"Open WebUI before 0.9.5 contains a stored cross-site scripting vulnerability in the OAuth authentication flow where the picture claim URL MIME type is inferred from file extension rather than Content-Type header, allowing SVG files to bypass the profile image validator and be stored as data URIs. Authenticated users who visit the profile image endpoint receive attacker-controlled SVG content with inline disposition and no default security headers, enabling script execution in the same origin to steal authentication tokens and achieve account takeover.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","score":8.5},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","score":9.0},"cwes":["CWE-20"],"references":["https://github.com/open-webui/open-webui/security/advisories/GHSA-3wgj-c2hg-vm6q","https://www.vulncheck.com/advisories/open-webui-stored-cross-site-scripting-via-oauth-picture-claim-svg-data-uri"],"products":["openwebui:open_webui"],"source":"nvd","synced_at":"2026-10-19T22:45:36.895656543+00:00"},"epss":{"cve":"CVE-2026-56398","score":0.00635,"percentile":0.50426,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-3wgj-c2hg-vm6q","url":"https://osv.dev/vulnerability/GHSA-3wgj-c2hg-vm6q","summary":"Open WebUI vulnerable to stored XSS via OAuth picture claim stored as SVG data URI in profile_image_url","modified":"2026-07-16T03:56:45.437973308Z","packages":[{"ecosystem":"PyPI","name":"open-webui","purl":"pkg:pypi/open-webui","ranges":["<0.9.5"],"fixed":["0.9.5"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}