CVE-2025-9086

HIGH

curl Secure Cookie Path - Heap Buffer Overread

Title source: manual
STIX 2.1

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.

Scores

CVSS v3 7.5
EPSS 0.0130
EPSS Percentile 66.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-125
Status published
Products (6)
curl/curl 8.13.0
curl/curl 8.14.0
curl/curl 8.14.1
curl/curl 8.15.0
debian/debian_linux 11.0
haxx/curl 8.13.0 - 8.16.0
Published Sep 12, 2025
Tracked Since Feb 18, 2026