Vulnerability Description
libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. An easy handle that first uses default native CA trust can continue trusting the native platform store after the application switches that same handle to custom CA material for a later transfer.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Haxx | Curl | >= 8.17.0, < 8.21.0 |
Related Weaknesses (CWE)
References
- https://curl.se/docs/CVE-2026-11564.htmlPatchVendor Advisory
- https://curl.se/docs/CVE-2026-11564.jsonVendor Advisory
- https://hackerone.com/reports/3788984ExploitIssue TrackingThird Party Advisory
- https://hackerone.com/reports/3788984ExploitIssue TrackingThird Party Advisory
FAQ
What is CVE-2026-11564?
CVE-2026-11564 is a vulnerability with a CVSS score of 9.1 (CRITICAL). libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. An easy handle that first uses default native CA trust can continue ...
How severe is CVE-2026-11564?
CVE-2026-11564 has been rated CRITICAL with a CVSS base score of 9.1/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-11564?
Check the references section above for vendor advisories and patch information. Affected products include: Haxx Curl.