{"cve":"CVE-2026-6733","nvd":{"published":"2026-06-17T18:18:05.473","modified":"2026-06-27T23:46:06.553","status":"Analyzed","description":"Impact:\nUndici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests.\n\nThis requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse.\n\nPatches:\nUpgrade to undici v6.26.0, v7.28.0 or v8.5.0.\n\nWorkarounds:\nDisable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","score":3.7},"cwes":["CWE-367"],"references":["https://cna.openjsf.org/security-advisories.html","https://github.com/nodejs/undici/security/advisories/GHSA-35p6-xmwp-9g52","https://hackerone.com/reports/3582376"],"products":["nodejs:undici"],"source":"nvd","synced_at":"2026-10-19T22:39:28.638635428+00:00"},"epss":{"cve":"CVE-2026-6733","score":0.0022,"percentile":0.12538,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-35p6-xmwp-9g52","url":"https://osv.dev/vulnerability/GHSA-35p6-xmwp-9g52","summary":"undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse","modified":"2026-09-10T03:51:07.666603424Z","packages":[{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":["<6.27.0"],"fixed":["6.27.0"]},{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":[">=7.0.0 <7.28.0"],"fixed":["7.28.0"]},{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":[">=8.0.0 <8.5.0"],"fixed":["8.5.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}