Vulnerability in the OpenSSH GSSAPI delta included in various Linux distributions. This vulnerability affects the GSSAPI patches added by various Linux distributions and does not affect the OpenSSH upstream project itself. The usage of sshpkt_disconnect() on an error, which does not terminate the process, allows an attacker to send an unexpected GSSAPI message type during the GSSAPI key exchange to the server, which will call the underlying function and continue the execution of the program without setting the related connection variables. As the variables are not initialized to NULL the code later accesses those uninitialized variables, accessing random memory, which could lead to undefined behavior. The recommended workaround is to use ssh_packet_disconnect() instead, which does terminate the process. The impact of the vulnerability depends heavily on the compiler flag hardening configuration.
This issue has been addressed in the following products: Red Hat Enterprise Linux 10 Via RHSA-2026:6463 https://access.redhat.com/errata/RHSA-2026:6463
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2026:6461 https://access.redhat.com/errata/RHSA-2026:6461
This issue has been addressed in the following products: Red Hat Enterprise Linux 9 Via RHSA-2026:6462 https://access.redhat.com/errata/RHSA-2026:6462
This issue has been addressed in the following products: Red Hat Enterprise Linux 10.0 Extended Update Support Via RHSA-2026:7107 https://access.redhat.com/errata/RHSA-2026:7107
This issue has been addressed in the following products: Red Hat Enterprise Linux 9.6 Extended Update Support Via RHSA-2026:9415 https://access.redhat.com/errata/RHSA-2026:9415
This issue has been addressed in the following products: Red Hat Enterprise Linux 9.4 Extended Update Support Via RHSA-2026:9732 https://access.redhat.com/errata/RHSA-2026:9732
This issue has been addressed in the following products: Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Via RHSA-2026:10714 https://access.redhat.com/errata/RHSA-2026:10714