CVE-2026-56400: Open WebUI — HIGH

open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests...

Full CISO analysis pending enrichment.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
Open WebUI	pip	—	No patch
145.1K 4 dependents Pushed 4d ago 66% patched ~5d to patch Full package profile →

Do you use Open WebUI? You're affected.

How severe is it?

CVSS 3.1

8.3 / 10

EPSS

N/A

Exploitation Status

No known exploitation

Sophistication

N/A

What is the attack surface?

AV Network

AC High

PR None

UI Required

S Changed

C High

I High

A High

What should I do?

No patch available

Monitor for updates. Consider compensating controls or temporary mitigations.

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is CVE-2026-56400?

open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests from attacker-controlled websites when an admin user visits them.

Is CVE-2026-56400 actively exploited?

No confirmed active exploitation of CVE-2026-56400 has been reported, but organizations should still patch proactively.

How to fix CVE-2026-56400?

No patch is currently available. Monitor vendor advisories for updates.

What is the CVSS score for CVE-2026-56400?

CVE-2026-56400 has a CVSS v3.1 base score of 8.3 (HIGH).

What are the technical details?

Original Advisory

open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests from attacker-controlled websites when an admin user visits them.

Weaknesses (CWE)

CWE-613 Insufficient Session Expiration Primary CWE-613 Insufficient Session Expiration

CWE-613 — Insufficient Session Expiration: According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization."