CVE-2026-59846

A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell metacharacters, exposing environment variables and causing unintended shell behavior.

CVSS v3 3.9 LOW

3.9^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.3 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

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-2026-59846	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498179	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 13:17

Updated : 2026-09-01 21:18

NVD link : CVE-2026-59846

Mitre link : CVE-2026-59846

CVE.ORG link : CVE-2026-59846

JSON object : View

Products Affected

redhat

enterprise_linux
hardened_images

libssh

libssh

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-77

Improper Neutralization of Special Elements used in a Command ('Command Injection')

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