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
https://access.redhat.com/security/cve/CVE-2026-59843
https://bugzilla.redhat.com/show_bug.cgi?id=2498176

Configurations

No configuration.

History

22 Jul 2026, 20:17

Type	Values Removed	Values Added
References		() https://access.redhat.com/errata/RHSA-2026:42922 -

21 Jul 2026, 13:17

Type	Values Removed	Values Added
CWE		CWE-400

21 Jul 2026, 12:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-21 12:18

Updated : 2026-07-22 20:17

NVD link : CVE-2026-59843

Mitre link : CVE-2026-59843

CVE.ORG link : CVE-2026-59843

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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