libcurl CA Trust Leakage via Persistent Connection Pool
CVE-2026-11564 Published on July 3, 2026

Native CA trust persist
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.

NVD

Vulnerability Analysis

CVE-2026-11564 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. Public availability of a proof of concept (POC) exploit exists for CVE-2026-11564. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality and integrity, and no impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
NONE

Products Associated with CVE-2026-11564

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Haxx Curl
 
Canonical Ubuntu Linux
 

Affected Versions

curl: