CVE-2026-82639 (GCVE-0-2026-82639)
Vulnerability from cvelistv5
Published
2026-08-30 13:23
Modified
2026-08-31 16:51
Severity ?
8.7 (High) - 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
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-20 - Improper Input Validation
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.
References
Impacted products
Vendor Product Version
ChatGPTNextWeb NextChat Version: 2.15.8   ≤ 2.16.1
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