Critical severity · published Jul 15, 2026
CVE-2026-56400
open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation
9.6
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
open-webui · open-webui
before 0.3.14 · source: vendor
OW
Open Webui · Openwebui
before 0.3.14 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-56400
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-56400
Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-6xcp-7mpr-m7wm
Exploit
https://www.vulncheck.com/advisories/open-webui-remote-code-execution-via-cors-misconfiguration-and-session-validation
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