Description
libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services".
libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead.
When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.
Metrics
CVSS 3.1 6.5/10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| curl | curl | >= 7.43.0, < 8.14.2; >= 8.15.0, < 8.16.1; >= 8.17.0, < 8.20.1 |
| curl | curl | >= 97c272e5d173ad5f706443e2477f0a84f0044edd, < 5e99b73cf441d9c369768b9cd48b5389b9a2503d |
| curl | curl | 8.20.0; 8.19.0; 8.18.0; 8.17.0; 8.16.0; 8.15.0; 8.14.1; 8.14.0; 8.13.0; 8.12.1; 8.12.0; 8.11.1; 8.11.0; 8.10.1; 8.10.0; 8.9.1; 8.9.0; 8.8.0; 8.7.1; 8.7.0 |
References
- https://curl.se/docs/CVE-2026-8458.htmlPatch, Vendor Advisory
- https://curl.se/docs/CVE-2026-8458.jsonVendor Advisory
- https://hackerone.com/reports/3721183Exploit, Issue Tracking, Third Party Advisory
- https://hackerone.com/reports/3721183Exploit, Issue Tracking, Third Party Advisory
Timeline
- Published
- Jul 3, 2026
- Last modified
- Sep 15, 2026
- NVD status
- Modified