1. A cookie is set using the `secure` keyword for `https://target`
2. curl is redirected to or otherwise made to speak with `http://target` (same
hostname, but using clear text HTTP) using the same cookie set
3. The same cookie name is set - but with just a slash as path (`path='/'`).
Since this site is not secure, the cookie *should* just be ignored.
4. A bug in the path comparison logic makes curl read outside a heap buffer
boundary
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.
2. curl is redirected to or otherwise made to speak with `http://target` (same
hostname, but using clear text HTTP) using the same cookie set
3. The same cookie name is set - but with just a slash as path (`path='/'`).
Since this site is not secure, the cookie *should* just be ignored.
4. A bug in the path comparison logic makes curl read outside a heap buffer
boundary
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.
Metrics
Affected Vendors & Products
No data.
No data.
No data.
No data.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 12 Sep 2025 05:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 1. A cookie is set using the `secure` keyword for `https://target` 2. curl is redirected to or otherwise made to speak with `http://target` (same hostname, but using clear text HTTP) using the same cookie set 3. The same cookie name is set - but with just a slash as path (`path='/'`). Since this site is not secure, the cookie *should* just be ignored. 4. A bug in the path comparison logic makes curl read outside a heap buffer boundary 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. | |
| Title | Out of bounds read for cookie path | |
| References |
|
MITRE
Status: PUBLISHED
Assigner: curl
Published:
Updated: 2025-09-12T05:10:03.815Z
Reserved: 2025-08-16T05:40:23.800Z
Link: CVE-2025-9086
Vulnrichment
No data.
NVD
Status : Received
Published: 2025-09-12T06:15:44.100
Modified: 2025-09-12T06:15:44.100
Link: CVE-2025-9086
Redhat
No data.
OpenCVE Enrichment
No data.