CVE-2026-11564

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 v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-11564.html	Patch Vendor Advisory
https://curl.se/docs/CVE-2026-11564.json	Vendor Advisory
https://hackerone.com/reports/3788984	Exploit Issue Tracking Third Party Advisory
https://hackerone.com/reports/3788984	Exploit Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-03 07:16

Updated : 2026-09-15 07:16

NVD link : CVE-2026-11564

Mitre link : CVE-2026-11564

CVE.ORG link : CVE-2026-11564

JSON object : View

Products Affected

haxx

curl

CWE

CWE-295

Improper Certificate Validation

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