Cookie scoped to parent domain
Summary: A cookie's domain attribute determines which domains can access it, and a cookie scoped to a parent domain is accessible by that parent and all of its subdomains. If the cookie holds sensitive data such as a session token, less trusted or less secure applications on those domains may be able to reach it, and PortSwigger rates the issue low severity (0x00500300).
Why it matters: A session token shared across every subdomain is only as safe as the weakest application hosted on any of them, so one compromised or neglected subdomain can expose credentials for the whole parent domain.
Read the original at PortSwigger Research ↗
- Topics
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