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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-55655 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
https://access.redhat.com/security/cve/CVE-2026-55655 Red Hat, Inc.
https://bugzilla.redhat.com/show_bug.cgi?id=2462250 Red Hat, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-923 Improper Restriction of Communication Channel to Intended Endpoints Red Hat, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-55655
NVD Published Date:
06/23/2026
NVD Last Modified:
06/23/2026
Source:
Red Hat, Inc.