{"id":"UBUNTU-CVE-2026-16729","details":"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.","modified":"2026-08-06T22:15:11.804727504Z","published":"2026-07-29T17:16:00Z","upstream":["CVE-2026-16729"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-16729"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-16729"},{"type":"REPORT","url":"https://github.com/nodejs/undici/security/advisories/GHSA-v3r7-h72x-cjcm"}],"affected":[{"package":{"name":"node-undici","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/node-undici?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1","5.26.3+dfsg1+~cs23.10.12-2"],"ecosystem_specific":{"binaries":[{"binary_name":"node-llhttp","binary_version":"9.1.3~5.26.3+dfsg1+~cs23.10.12-2"},{"binary_name":"node-undici","binary_version":"5.26.3+dfsg1+~cs23.10.12-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16729.json"}},{"package":{"name":"node-undici","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/node-undici?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.3.0+dfsg1+~cs24.12.11-2","7.16.0+dfsg+~cs3.2.0-2","7.18.2+dfsg+~cs3.2.0-1","7.18.2+dfsg+~cs3.2.0-1build1"],"ecosystem_specific":{"binaries":[{"binary_version":"7.18.2+dfsg+~cs3.2.0-1build1","binary_name":"node-undici"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16729.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}