CVE-2026-55655

A flaw was found in OpenSSH. A local unprivileged attacker on a Linux client host can hijack client-side X11 forwarding connections. This is possible by pre-binding the preferred abstract X socket name when X11 forwarding is enabled and a local UNIX-domain X socket is used. A successful attack can compromise the confidentiality of forwarded X11 traffic, including sensitive window contents and input, and may allow some manipulation of the forwarded session.

CVSS v3 5.0 MEDIUM

5.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:36759
https://access.redhat.com/errata/RHSA-2026:47755
https://access.redhat.com/errata/RHSA-2026:47756
https://access.redhat.com/errata/RHSA-2026:47757
https://access.redhat.com/errata/RHSA-2026:54387
https://access.redhat.com/errata/RHSA-2026:58981
https://access.redhat.com/security/cve/CVE-2026-55655	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2462250	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:openbsd:openssh:-:::::::*
	cpe:2.3:o:redhat:enterprise_linux:6.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:7.0:::::::*
	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 : 2026-06-23 04:17

Updated : 2026-09-01 09:16

NVD link : CVE-2026-55655

Mitre link : CVE-2026-55655

CVE.ORG link : CVE-2026-55655

JSON object : View

Products Affected

redhat

enterprise_linux

openbsd

openssh

CWE

CWE-923

Improper Restriction of Communication Channel to Intended Endpoints

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