ChatGPTNextWeb NextChat EUVD-2026-26797

Q: What is the CVSS score of EUVD-2026-26797?

EUVD-2026-26797 has a CVSS 4.0 base score of 2.1 (Low). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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. EPSS exploitation probability: 0.0%.

| CVE-2026-7643 LOW

Origin Validation Error (CWE-346)

2026-05-02 cna@vuldb.com

Information Disclosure

2.1

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

2.1 LOW

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

Analysis Generated

May 02, 2026 - 15:30 vuln.today

EUVD ID Assigned

May 02, 2026 - 15:22 euvd

EUVD-2026-26797

Analysis Generated

May 02, 2026 - 15:22 vuln.today

CVE Published

May 02, 2026 - 15:16 nvd

LOW 2.1

DescriptionCVE.org

A flaw has been found in ChatGPTNextWeb NextChat up to 2.16.1. This impacts an unknown function of the file Next.js of the component API Endpoint. Executing a manipulation can lead to permissive cross-domain policy with untrusted domains. The attack may be launched remotely. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

AnalysisAI

Permissive cross-domain policy in ChatGPTNextWeb NextChat up to version 2.16.1 allows remote attackers with user interaction to manipulate the Next.js API endpoint and enable untrusted domains to access application resources, leading to information disclosure. Public exploit code exists for this vulnerability, though the vendor has not yet responded to early disclosure notification.

Technical ContextAI

The vulnerability exists in the Next.js API endpoint component of ChatGPTNextWeb NextChat, specifically involving improper handling of cross-origin resource sharing (CORS) policies as classified under CWE-346 (Origin Validation Error). The flaw permits attackers to manipulate domain policies to allow requests from untrusted domains, bypassing the browser's same-origin policy safeguards. This represents a failure to properly validate and restrict the origins from which the API will accept requests, a common misconfiguration in web applications built with Next.js that do not implement strict CORS headers or origin validation logic.

RemediationAI

Upgrade ChatGPTNextWeb NextChat to a version released after 2.16.1 once a patched release becomes available. Until an official patch is released, implement strict CORS policy configuration by explicitly defining allowed origins in the Next.js API configuration-restrict the Access-Control-Allow-Origin header to only trusted domains rather than using wildcard (*) or dynamic origin acceptance without validation. Additionally, review and restrict the Access-Control-Allow-Credentials header to prevent credential-bearing requests from untrusted origins. For immediate risk reduction without requiring application code changes, deploy a Web Application Firewall (WAF) rule to reject requests from unauthorized origins to API endpoints, though this requires monitoring logs to identify legitimate origins and may impact legitimate cross-domain integrations. Monitor the GitHub issue (https://github.com/ChatGPTNextWeb/NextChat/issues/6756) and project releases for availability of a patched version.