secure
keyword for https://target
http://target
(same
hostname, but using clear text HTTP) using the same cookie setpath="/"
).
Since this site is not secure, the cookie should just be ignored.The bug either causes a crash or it potentially makes the comparison come to the wrong conclusion and lets the clear-text site override the contents of the secure cookie, contrary to expectations and depending on the memory contents immediately following the single-byte allocation that holds the path.
The presumed and correct behavior would be to plainly ignore the second set of the cookie since it was already set as secure on a secure host so overriding it on an insecure host should not be okay.
{ "last_affected": "8.15.0", "package": "curl", "issue": "https://hackerone.com/reports/3294999", "severity": "Low", "www": "https://curl.se/docs/CVE-2025-9086.html", "affects": "lib", "CWE": { "id": "CWE-125", "desc": "Out-of-bounds Read" }, "URL": "https://curl.se/docs/CVE-2025-9086.json", "award": { "amount": "505", "currency": "USD" } }