CVE-2026-45665

CVE-2026-45665 is a high-severity vulnerability in Openwebui Open Webui with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.0, a Stored Cross-Site Scripting (XSS) vulnerability exists in the Banner component due to an improper sanitization order (specifically, DOMPurify is executed before the marked library). This vulnerability allows a compromised or malicious administrator to plant a malicious payload in the global banner. Crucially, this vector enables Privilege Escalation, as the malicious banner is rendered for all users, including the Super Admin (Primary Admin). Consequently, the payload successfully bypasses the existing security mechanism. An attacker can leverage this to steal the Super Admin's session token This vulnerability is fixed in 0.8.0.

Frequently asked questions

What is CVE-2026-45665?
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.0, a Stored Cross-Site Scripting (XSS) vulnerability exists in the Banner component due to an improper sanitization order (specifically, DOMPurify is executed before the marked library). This vulnerability allows a compromised or malicious administrator to plant a malicious payload in the global banner. Crucially, this vector enables Privilege Escalation, as the malicious banner is rendered for all users, including the Super Admin (Primary Admin). Consequently, the payload successfully bypasses the existing security mechanism. An attacker can leverage this to steal the Super Admin's session token This vulnerability is fixed in 0.8.0.
How severe is CVE-2026-45665?
CVE-2026-45665 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-45665 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45665?
CVE-2026-45665 affects Openwebui Open Webui. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45665?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-45665 have an EU (EUVD) identifier?
Yes. CVE-2026-45665 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30664.
When was CVE-2026-45665 published?
CVE-2026-45665 was published on 2026-05-15 and last updated on 2026-06-17.

References

Affected products (1)

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