CVE-2026-59843

A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CHANNEL_OPEN, causing later channel writes to loop indefinitely and consume CPU, leading to denial of service.

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 NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:42922	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:55855
https://access.redhat.com/errata/RHSA-2026:62217
https://access.redhat.com/errata/RHSA-2026:62218
https://access.redhat.com/security/cve/CVE-2026-59843	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498176	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:libssh:libssh:-:::::::*
	cpe:2.3:a:redhat:hardened_images:-:::::::*
	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:9.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:10.0:::::::*

History

No history.

Information

Published : 2026-07-21 12:18

Updated : 2026-09-01 21:18

NVD link : CVE-2026-59843

Mitre link : CVE-2026-59843

CVE.ORG link : CVE-2026-59843

JSON object : View

Products Affected

redhat

enterprise_linux
hardened_images

libssh

libssh

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

CWE-400

Uncontrolled Resource Consumption

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