A subdomain can remove the Host-Only flag from an existing cookie to a parent domain.
A user accessing untrusted subdomains could see their Host-Only protections stripped from cookies. Given most usecases won't reflect these cookies to a browser, the impact is limited.
{
"cwe_ids": [
"CWE-565"
],
"github_reviewed": true,
"github_reviewed_at": "2026-10-20T19:58:14Z",
"nvd_published_at": "2026-10-19T17:17:04Z",
"severity": "LOW"
}