{"cve":"CVE-2026-16729","nvd":{"published":"2026-07-29T17:16:51.123","modified":"2026-08-05T15:18:55.053","status":"Analyzed","description":"undici's setCookie function does not fully sanitize cookie attributes. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a domain value is not checked for semicolons and entries in the unparsed array are not sanitized, so attacker-influenced input can inject additional cookie attributes. For example, a domain value containing a semicolon can append attributes such as SameSite, and an unparsed entry can inject attributes such as HttpOnly, without the caller setting them. Applications that pass user-controlled input to these fields, such as multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, or the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","score":6.5},"cwes":["CWE-74"],"references":["https://cna.openjsf.org/security-advisories.html","https://github.com/nodejs/undici/security/advisories/GHSA-v3r7-h72x-cjcm"],"products":["nodejs:undici"],"source":"nvd","synced_at":"2026-10-19T22:46:40.600842820+00:00"},"epss":{"cve":"CVE-2026-16729","score":0.00278,"percentile":0.20316,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-v3r7-h72x-cjcm","url":"https://osv.dev/vulnerability/GHSA-v3r7-h72x-cjcm","summary":"undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields","modified":"2026-09-10T03:51:14.535204629Z","packages":[{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":["<6.28.0"],"fixed":["6.28.0"]},{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":[">=7.0.0 <7.29.0"],"fixed":["7.29.0"]},{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici","ranges":[">=8.0.0 <8.9.0"],"fixed":["8.9.0"]}]}],"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."]}