RHSA-2026:85958MediumCVSS 6.5

Red Hat Security Advisory: openssh security update

Published
October 20, 2026
Last Modified
October 20, 2026

🔗 CVE IDs covered (3)

CVE-2026-59997 →CVE-2026-59998 →CVE-2026-60000 →

📋 Description

CVE-2026-59997 — openssh: OpenSSH: SFTP security bypass due to command-line argument parsing flaw CVE-2026-59998 — openssh: OpenSSH: Undocumented GSSAPIStrictAcceptorCheck behavior impacts security in Windows Active Directory CVE-2026-60000 — openssh: OpenSSH: Denial of Service via excessive GSSAPI authentication attempts

🎯 Affected products91

  • Red Hat Enterprise Linux AppStream (v. 9)
  • Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-0:9.9p1-13.el9_8.src as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-askpass-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-askpass-debuginfo-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.aarch64 as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.s390x as a component of Red Hat Enterprise Linux BaseOS (v. 9)
  • openssh-clients-debuginfo-0:9.9p1-13.el9_8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)
  • +61 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: To mitigate this issue, ensure that all security-relevant command-line arguments for the `internal-sftp` server are positioned within the first nine arguments. Alternatively, consider using the default SFTP server implementation if custom configurations relying on numerous arguments are not strictly necessary. If `internal-sftp` is used with more than nine arguments, verify that no critical security options are being silently discarded. Workaround: 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. ```bash # echo "GSSAPIAuthentication no" >> /etc/ssh/sshd_config # systemctl restart sshd ``` Alternatively, 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.

🔗 References (6)