CVE-2026-55655
Status: ModifiedMedium (6.1)—
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
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
- Base score: 6.1
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.12%
- Percentile among all scored CVEs: 2
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-923
References
- 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
- https://bugzilla.redhat.com/show_bug.cgi?id=2462250
Raw JSON (NVD)
Show
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