CVE-2026-86414
Published:October 20, 2026
Updated:November 02, 2026
An HTTP proxy can trick libcurl into sending the origin's credentials (Basic
password, or a Negotiate/Kerberos ticket) to the proxy itself, by answering
the "CONNECT" tunnel request with 401 "WWW-Authenticate:" instead of the
expected 407 "Proxy-Authenticate:".
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)
Insertion of Sensitive Information Into Sent Data
EPSS
Base Score:
0.68