Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV N L N L P H H N 8.5 .0042 34.9 —
AFFECTED Product Versions Fixed open-webui unspecified 0.9.5
TIMELINE Jun 21 Reserved by VulnCheck Jul 15 EXPLOIT PUBLISHED — CVE-2026-56398 (open-webui). Public exploit reference added. Jul 15 Published (CNA: VulnCheck)
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.
| Date | Event | Detail |
|---|---|---|
| June 21, 2026 | Reserved | Reserved by VulnCheck |
| July 15, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-56398 (open-webui). Public exploit reference added. |
| July 15, 2026 | Published | Published (CNA: VulnCheck) |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| open-webui | open-webui | — | — | 0.9.5 |
Authoritative record: CVE-2026-56398 at cve.org
Vendors: open-webui
Weaknesses: CWE-20
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-56398 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.