SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-44549

Prior to 0.8.0, Excel file attachments are previewed in an unsafe way.

HIGH 8.7EPSS 0.32%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.32%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.0, Excel file attachments are previewed in an unsafe way. A crafted XLSX file payload can be used to cause the sheetjs function sheet_to_html to embed an XSS payload into the generated HTML. This is subsequently added to the DOM unsanitized via @html causing the payload to trigger. This vulnerability is fixed in 0.8.0.

CVSS 3.1
8.7 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
EPSS
0.32% probability · 25th percentile
CISA KEV
Not listed
Weakness
CWE-79
Affected
openwebui/open webui
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.