CVE-2026-59849

A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service.

CVSS v3 3.1 LOW

3.1^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.6 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:42922	Issue Tracking
https://access.redhat.com/security/cve/CVE-2026-59849	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498182	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:10.0:::::::*

History

30 Jul 2026, 16:33

Type	Values Removed	Values Added
CPE		cpe:2.3:a:redhat:hardened_images:-:::::::* cpe:2.3:o:redhat:enterprise_linux:10.0:::::::* cpe:2.3:a:libssh:libssh:-:::::::*
References	~~() https://access.redhat.com/errata/RHSA-2026:42922 -~~	() https://access.redhat.com/errata/RHSA-2026:42922 - Issue Tracking
References	~~() https://access.redhat.com/security/cve/CVE-2026-59849 -~~	() https://access.redhat.com/security/cve/CVE-2026-59849 - Vendor Advisory
References	~~() https://bugzilla.redhat.com/show_bug.cgi?id=2498182 -~~	() https://bugzilla.redhat.com/show_bug.cgi?id=2498182 - Issue Tracking, Vendor Advisory
First Time		Libssh libssh Redhat enterprise Linux Redhat hardened Images Redhat Libssh

22 Jul 2026, 20:17

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

21 Jul 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-21 15:16

Updated : 2026-07-30 16:33

NVD link : CVE-2026-59849

Mitre link : CVE-2026-59849

CVE.ORG link : CVE-2026-59849

JSON object : View

Products Affected

redhat

hardened_images
enterprise_linux

libssh

libssh

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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