CVE-2026-45318

🔶 medium

Summary

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.

CVSS Score

5.4

Medium

EPSS Score

0.0

Exploit Probability

Published Date

2026-05-15

First Seen: 2026-05-17

📊 Relative Risk Intelligence

This CVE is Lower Risk - more severe than 22.4% of all 349,016 vulnerabilities in our database.

#270,989

Below average severity

Severity Percentile

🎯 CISA SSVC Assessment Updated: May 18, 2026

🔍 Exploitation Status

Poc

Proof-of-concept available

⚙️ Automatable

Requires human interaction

💥 Technical Impact

Partial

Limited system impact

SSVC data provided by CISA

Last Modified 2026-05-18

Source NVD 🔗

CVSS Vector 3.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CWE IDs (Weakness Types)

CWE-79

📦 Affected Products 1

Vendor	Product	Status	Affected Versions
openwebui	open_webui	Affected	< 0.9.3

🔗 References 1

https://github.com/open-webui/open-webui/security/ad...

Exploit Mitigation Vendor Advisory

🔗 Related CVEs 6

CVE ID	Severity	CVSS	EPSS	Summary	Published
CVE-2026-56398	⚠️ high	7.3	0.3	Open WebUI before 0.9.5 contains a stored cross-site scripting vulnerability in the OAuth authentication flow where the ...	2026-07-15
CVE-2026-56400	⚠️ high	8.3	0.3	open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow...	2026-07-15
CVE-2026-59212	🔶 medium	5.4	0.3	Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 before 0.10.0, _verify_...	2026-07-09
CVE-2026-59213	ℹ️ low	3.5	0.3	Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.6.27 before 0.10.0, get_all...	2026-07-09
CVE-2026-59214	⚠️ high	7.3	0.3	Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, Open WebUI runs c...	2026-07-09
CVE-2026-59215	ℹ️ low	3.1	0.3	Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, channel thread pa...	2026-07-09

These CVEs affect the same products