{"id":"CVE-2026-82639","summary":"NextChat 2.15.8 through 2.16.1 OpenAI API Key Disclosure","details":"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.","modified":"2026-09-02T03:30:45.035434396Z","published":"2026-08-30T13:23:39.106Z","database_specific":{"cwe_ids":["CWE-20"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82639.json","cna_assigner":"VulnCheck"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82639.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82639"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/nextchat-2.15.8-through-2.16.1-openai-api-key-disclosure"},{"type":"REPORT","url":"https://github.com/ChatGPTNextWeb/NextChat/issues/6814"},{"type":"PACKAGE","url":"https://github.com/ChatGPTNextWeb/NextChat"},{"type":"ARTICLE","url":"https://github.com/ChatGPTNextWeb/NextChat/blob/v2.16.1/app/api/proxy.ts"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/chatgptnextweb/nextchat","events":[{"introduced":"38fa3056df5fd9db915a9d4d1c5e11477de22ff6"},{"fixed":"557a2cce357749c6fb3176d42e03ff6f7de4d355"}],"database_specific":{"extracted_events":[{"introduced":"2.15.8"},{"last_affected":"2.16.1"},{"fixed":"2.16.1"}],"source":["AFFECTED_FIELD","DESCRIPTION"]}}],"versions":["v2.16.0","v2.15.8"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-82639.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"}]}