CVE-2026-82639EPSS p41.3%
CVE-2026-82639CVE-2026-82639
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.
Scoring
| CVSS | 7.5 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| EPSS | 0.51% probability of exploitation · percentile 41.3% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-10 |