CVE-2026-56400

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.52% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 43.9% of scored records. A rank, not a probability.

NVD base score

9.0 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Analyzed. NVD last modified this record on 2026-07-16.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-07-15 11:25Z3 MO AGO

Last updated

2026-07-15 18:33Z3 MO AGO

Reserved

2026-06-21

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Critical (CVSS 9.0)

CNA CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Weaknesses

• CWE-613Insufficient Session ExpirationBase

Data version

5.2

Document digest

274bab99c4b2b34250feaed8733316c20af094821693d21402cca5dd16dc0b83

• github.comGitHub Security Advisory (GHSA-6xcp-7mpr-m7wm)https://github.com/open-webui/open-webui/security/advisories/GHSA-6xcp-7mpr-m7wmvendor-advisory
• www.vulncheck.comVulnCheck Advisory: open-webui - Remote Code Execution via CORS Misconfiguration and Session Validationhttps://www.vulncheck.com/advisories/open-webui-remote-code-execution-via-cors-misconfiguration-and-session-validationthird-party-advisory