CVE-2026-87866
Published:October 20, 2026
Updated:November 02, 2026
When built with wolfSSL, curl can successfully validate a pinned public key
hash against a key the TLS peer does not possess. During the TLS handshake,
wolfSSL validates the connection, but curl's subsequent re-parsing of the same
certificate - tricked by a manipulated validity length field - extracts and
matches a different embedded key, incorrectly authorizing the pinned public
key.
Affected Packages
libcurl (CONAN):
Affected version(s) =8.22.0 <8.23.0Fix Suggestion:
Update to version 8.23.0https://github.com/curl/curl.git (GITHUB):
Affected version(s) =curl-8_22_0 <curl-8_23_0Fix Suggestion:
Update to version curl-8_23_0Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
9.1
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Improper Certificate Validation
EPSS
Base Score:
0.51