CVE-2026-19931
Published:September 02, 2026
Updated:September 02, 2026
libcurl Negotiate ambient user connection reuse: libcurl incorrectly reuses HTTP connections authenticated with Negotiate when the initial request used empty credentials, so one user's request can traverse another user's authenticated connection. Affects curl 7.64.1 through 8.21.0, fixed in 8.22.0.
Affected Packages
libcurl (CONAN):
Affected version(s) >=7.76.0 <8.22.0Fix Suggestion:
Update to version 8.22.0https://github.com/curl/curl.git (GITHUB):
Affected version(s) >=curl-7_64_1 <curl-8_22_0Fix Suggestion:
Update to version curl-8_22_0Related Resources (2)
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Contact UsCVSS v4
Base Score:
6
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
PRESENT
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Exposure of Data Element to Wrong Session