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CVE-2026-55655

medium

A flaw was found in OpenSSH.

Vendor / product: Openbsd — openssh

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
6.1
6.1 (CVSS v3.1)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-06-23 04:17
Modified: 2026-10-29 23:16
NVD status: Modified
Last synced 7 hours ago
Verified against the source API 2026-10-29 23:32 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

openbsd / openssh all versions
redhat / enterprise_linux 6.0, 7.0, 8.0, 9.0, 10.0

Weakness classification (CWE)

CWE-923

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://access.redhat.com/security/cve/CVE-2026-55655
Vendor advisory: https://bugzilla.redhat.com/show_bug.cgi?id=2462250

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-29 23:32 UTC · record ↗

Learn the basics

Understanding CVEs and CVSS Scores

Related CVEs

CVE-2026-55653CVE-2026-60002CVE-2026-106583CVE-2026-106585CVE-2023-38408