{
  "threat_severity" : "Moderate",
  "public_date" : "2026-07-08T00:11:05Z",
  "bugzilla" : {
    "description" : "openssh: OpenSSH: Undocumented GSSAPIStrictAcceptorCheck behavior impacts security in Windows Active Directory",
    "id" : "2497935",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2497935"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
    "status" : "verified"
  },
  "cwe" : "CWE-909",
  "details" : [ "sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no value if the server is in Windows Active Directory.", "A flaw was found in OpenSSH. The sshd component has an undocumented security-relevant behavior where GSSAPIStrictAcceptorCheck has no value when the server is in a Windows Active Directory environment. This could lead to unintended information disclosure and impact data integrity." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Hardened Images",
    "release_date" : "2026-07-09T00:00:00Z",
    "advisory" : "RHSA-2026:37382",
    "cpe" : "cpe:/a:redhat:hummingbird:1",
    "package" : "openssh-main-10.4p1-1.hum1",
    "impact" : "moderate"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "openssh",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Fix deferred",
    "package_name" : "openssh",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "openssh",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "openssh",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "openssh",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Fix deferred",
    "package_name" : "openshift/ose-rhel-coreos-8",
    "cpe" : "cpe:/a:redhat:openshift:4"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4",
    "fix_state" : "Fix deferred",
    "package_name" : "openshift/ose-rhel-coreos-9",
    "cpe" : "cpe:/a:redhat:openshift:4"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-59998\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-59998\nhttps://marc.info/?l=openssh-unix-dev&m=178333966933090&w=2\nhttps://www.openssh.org/releasenotes.html#10.4p1\nhttps://www.openwall.com/lists/oss-security/2026/07/06/5" ],
  "name" : "CVE-2026-59998",
  "mitigation" : {
    "value" : "To mitigate this issue, avoid using GSSAPI authentication for `sshd` when the server is integrated with a Windows Active Directory environment. If GSSAPI authentication is not strictly required, it can be disabled by setting `GSSAPIAuthentication no` in the `/etc/ssh/sshd_config` file. After modifying the configuration, the `sshd` service must be restarted for the changes to take effect. Note that restarting the `sshd` service will terminate all active SSH sessions.\n```bash\n# echo \"GSSAPIAuthentication no\" >> /etc/ssh/sshd_config\n# systemctl restart sshd\n```\nAlternatively, if GSSAPI authentication is necessary in such an environment, ensure that the network path between the client and the `sshd` server, and to the Active Directory, is secured and trusted to prevent man-in-the-middle attacks.",
    "lang" : "en:us"
  },
  "csaw" : false
}