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RLSA-2026:47755 (CVE-2026-55653)

Vulnerability from osv_rocky – Published: 2026-07-30 12:00 – Updated: 2026-08-13 12:10 – Source website
VLAI
Summary
Moderate: openssh security update
Details

OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems. It includes the core files necessary for both the OpenSSH client and server.

Security Fix(es):

  • openssh: Local MITM of X11 forwarding via abstract UNIX socket pre-binding in Rocky Linux OpenSSH client versions (CVE-2026-55655)

  • openssh: Double free in Rocky Linux versions of OpenSSH DH-GEX client path during FIPS known-group validation leads to client-side denial of service (CVE-2026-55653)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity
5.0 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:L/A:N
Credits
Rocky Enterprise Software Foundation
Red Hat
References
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "openssh",
        "purl": "pkg:rpm/rocky-linux/openssh?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "BaseOS"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:8.0p1-30.el8_10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:47755"
  },
  "details": "OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems. It includes the core files necessary for both the OpenSSH client and server.\n\nSecurity Fix(es):\n\n* openssh: Local MITM of X11 forwarding via abstract UNIX socket pre-binding in Rocky Linux OpenSSH client versions (CVE-2026-55655)\n\n* openssh: Double free in Rocky Linux versions of OpenSSH DH-GEX client path during FIPS known-group validation leads to client-side denial of service (CVE-2026-55653)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:47755",
  "modified": "2026-08-13T12:10:04.071322Z",
  "published": "2026-07-30T12:00:53.025496Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:47755"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2462250"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2462351"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:47755"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Moderate: openssh security update",
  "upstream": [
    "CVE-2026-55653",
    "CVE-2026-55655"
  ]
}



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