CVE-2026-59851

A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:42922	Issue Tracking
https://access.redhat.com/security/cve/CVE-2026-59851	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498184	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, 16:08

Type	Values Removed	Values Added
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-2026-59851 -~~	() https://access.redhat.com/security/cve/CVE-2026-59851 - Vendor Advisory
References	~~() https://bugzilla.redhat.com/show_bug.cgi?id=2498184 -~~	() https://bugzilla.redhat.com/show_bug.cgi?id=2498184 - Issue Tracking, Vendor Advisory
CPE		cpe:2.3:a:redhat:hardened_images:-:::::::* cpe:2.3:o:redhat:enterprise_linux:10.0:::::::* cpe:2.3:a:libssh:libssh:-:::::::*
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 16:08

NVD link : CVE-2026-59851

Mitre link : CVE-2026-59851

CVE.ORG link : CVE-2026-59851

JSON object : View

Products Affected

redhat

hardened_images
enterprise_linux

libssh

libssh

CWE

CWE-863

Incorrect Authorization

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