FKIE_CVE-2026-55655

Vulnerability from fkie_nvd - Published: 2026-06-23 04:17 - Updated: 2026-09-01 09:16
Severity
5.0 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:L/A:N
6.1 (Medium) - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Summary
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.
References
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:36759
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:47755
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:47756
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:47757
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:54387
secalert@redhat.comhttps://access.redhat.com/errata/RHSA-2026:58981
secalert@redhat.comhttps://access.redhat.com/security/cve/CVE-2026-55655Vendor Advisory
secalert@redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2462250Issue Tracking, Vendor Advisory
Impacted products
Vendor Product Version
openbsd openssh -
redhat enterprise_linux 6.0
redhat enterprise_linux 7.0
redhat enterprise_linux 8.0
redhat enterprise_linux 9.0
redhat enterprise_linux 10.0
To clipboard 

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  "cveTags": [],
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    }
  ],
  "id": "CVE-2026-55655",
  "lastModified": "2026-09-01T09:16:45.167",
  "metrics": {
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        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
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          "privilegesRequired": "LOW",
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          "userInteraction": "REQUIRED",
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            {
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          "role": "CISA Coordinator",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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