CVE-2026-8932
libcurl: libcurl: Security feature bypass due to improper mTLS connection reuse
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 3, 2026
Updated · November 4, 2026
Description
A flaw was found in curl. The libcurl library, used for transferring data with URLs, could improperly reuse existing network connections. This occurred even when changes to mutual Transport Layer Security (mTLS) settings, particularly those for client certificates, should have prevented such reuse. This issue could lead to a security feature bypass, where a client might use a connection with an unintended or weaker security configuration, potentially compromising the integrity or confidentiality of data.
Statement
This is an Important security feature bypass in libcurl where mTLS connection reuse may occur despite changes to client certificate settings. This could lead to applications using libcurl with mTLS to inadvertently use a less secure connection than intended, potentially compromising data confidentiality or integrity. This issue primarily affects applications that dynamically alter mTLS client certificate configurations and reuse connections.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE-1025 · Comparison Using Wrong Factors