CVE-2026-8927
Published:July 03, 2026
Updated:July 21, 2026
When reusing a libcurl handle for sequential transfers driven by
environment-variable proxy configuration, libcurl fails to clear the proxy
authentication state between requests. Specifically, if the initial transfer
authenticates against "proxyA" using Digest auth, a subsequent transfer routed
through "proxyB" erroneously leaks the "Proxy-Authorization:" header intended
solely for "proxyA".
Affected Packages
https://github.com/curl/curl.git (GITHUB):
Affected version(s) >=curl-7_12_0 <curl-8_21_0Fix Suggestion:
Update to version curl-8_21_0Related Resources (3)
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)
Authentication Bypass by Capture-replay
EPSS
Base Score:
0.75