Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, his advisory tracks a regression of the original Excel-preview XSS (CVE-2026-44549). The same root cause — XLSX.utils.sheet_to_html() output rendered via {@html excelHtml} without DOMPurify — was reintroduced sometime after v0.8.0 and is exploitable again This vulnerability is fixed in 0.9.3.
Affected products
openwebui: open webui
References2
- github.com/open-webui/open-webui/security/advisories/GHSA-hcwp-… ExploitMitigationVendor Advisory
- github.com/open-webui/open-webui/security/advisories/GHSA-hcwp-… ExploitMitigationVendor Advisory
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 11 · as of 14 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
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