CVE-2026-82639 (GCVE-0-2026-82639)
Vulnerability from cvelistv5 – Published: 2026-08-30 13:23 – Updated: 2026-09-24 14:20
VLAI
EPSS
VEX
Title
NextChat 2.15.8 through 2.16.1 OpenAI API Key Disclosure
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-31 16:51 UTC
CWE
- CWE-20 - Improper Input Validation
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/ChatGPTNextWeb/NextChat/issues/6814 | issue-tracking |
| https://github.com/ChatGPTNextWeb/NextChat | product |
| https://github.com/ChatGPTNextWeb/NextChat/blob/v… | technical-description |
| https://www.vulncheck.com/advisories/nextchat-2.1… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| ChatGPTNextWeb | NextChat |
Affected:
2.15.8 , ≤ 2.16.1
(semver)
cpe:2.3:a:nextchat:nextchat:*:*:*:*:*:*:*:* |
Date Public
2026-07-05 00:00
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