CVE-2026-56400open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation

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.

9.0 CRITICALEPSS 0.52%Not in KEVNVD: Analyzed

Last updated: 2026-07-16 20:03 UTC

OverviewCVSS details

9.0CRITICALCVSS 4.0

Score source: VulnCheck (CNA)
NVD status: Analyzed
Published: Jul 15, 2026
Assigner: VulnCheck

Affected

open-webui (open-webui)

Versions: before 0.3.14
Fixed in: 0.3.14

Exploitation

Public exploit: Yes · 1 reference
CISA KEV: Not listed
KEV due date: —
SSVC: Exploitation poc · Automatable no · Impact total

EPSS · FIRST, scored Nov 7

0.52%chance of exploitation in 30 days

Higher than 44.42% of CVEs

CVSS 4.0 · VulnCheck (CNA)

9.0Critical

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

Attack vector: Network
Attack complexity: High
Attack requirements: Present
Privileges required: None
User interaction: Passive
Confidentiality impact: High
Integrity impact: High
Availability impact: High
Confidentiality (other systems): High
Integrity (other systems): High
Availability (other systems): High

CVSS 3.1 · NVD

9.6Critical

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

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Changed
Confidentiality impact: High
Integrity impact: High
Availability impact: High

CVSS 3.1 · VulnCheck (CNA)

8.3High

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

Attack vector: Network
Attack complexity: High
Privileges required: None
User interaction: Required
Scope: Changed
Confidentiality impact: High
Integrity impact: High
Availability impact: High

NVD status: Analyzed

Overview Affected Products References

NVD CVE.org

Overview

Severity

Score	Severity	Version	Vector String
9.0	CRITICAL	4.0VulnCheck (CNA)	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
9.6	CRITICAL	3.1NVD	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
8.3	HIGH	3.1VulnCheck (CNA)	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H

Details

CVE ID: CVE-2026-56400
Status: Analyzed
Assigner (CNA): VulnCheck
Published: Jul 15, 2026
Last modified: 2026-07-16 20:03 UTC
Weaknesses: CWE-613 · Insufficient Session Expiration

Sources

Refreshed hourly from the sources above. Last fetched 2026-11-08 08:21 UTC.