CVE-2026-55655

Published Jun 23, 2026

Last updated a day ago

CVSS medium 5.0

Overview

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.
Source
secalert@redhat.com
NVD status
Analyzed
Products
openssh, enterprise_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
6.1
Impact score
4.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Severity
MEDIUM

Weaknesses

secalert@redhat.com
CWE-923

Social media

Hype score
Not currently trending

  1. 🚨*CVE* 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 t… https://t.co/qnJHIeWUv1 ----- Traducción: CVE-2026-55655 Se … https://t.co/utmtNg

    @infoflowcloud

    23 Jun 2026

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.