CVE-2026-8458

libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-8458.html	Patch Vendor Advisory
https://curl.se/docs/CVE-2026-8458.json	Vendor Advisory
https://hackerone.com/reports/3721183	Exploit Issue Tracking Third Party Advisory
https://hackerone.com/reports/3721183	Exploit Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-03 07:16

Updated : 2026-09-15 07:16

NVD link : CVE-2026-8458

Mitre link : CVE-2026-8458

CVE.ORG link : CVE-2026-8458

JSON object : View

Products Affected

haxx

curl

CWE

CWE-488

Exposure of Data Element to Wrong Session

NVD-CWE-noinfo

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