CVE-2026-82639

Published: Aug 30, 2026Modified: Aug 31, 2026

8.7

Vector

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

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

Source: disclosure@vulncheck.com (Secondary)

Description

NextChat versions from 2.15.8 through 2.16.1 contain an improper URL validation vulnerability in the proxy endpoint that allows attackers to obtain the server's OpenAI API key. The x-base-url header is validated using substring matching instead of hostname parsing, allowing any URL containing 'api.openai.com' to pass validation and receive the server's credentials in the Authorization header.

Related CWEs

CWE-20

Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

References (5)

https://github.com/ChatGPTNextWeb/NextChat

Source: disclosure@vulncheck.com

https://github.com/ChatGPTNextWeb/NextChat/blob/v2.16.1/app/api/proxy.ts

Source: disclosure@vulncheck.com

https://github.com/ChatGPTNextWeb/NextChat/issues/6814

Source: disclosure@vulncheck.com

https://www.vulncheck.com/advisories/nextchat-2.15.8-through-2.16.1-openai-api-key-disclosure

Source: disclosure@vulncheck.com

https://github.com/ChatGPTNextWeb/NextChat/issues/6814

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Timeline

No history available yet.