OpenSSH GSSAPI: Uninitialized Variables via sshpkt_disconnect
CVE-2026-3497 Published on March 12, 2026

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.

NVD

Vulnerability Analysis

CVE-2026-3497 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
LOW
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Types

Use of Uninitialized Resource

The software uses or accesses a resource that has not been initialized. When a resource has not been properly initialized, the software may behave unexpectedly. This may lead to a crash or invalid memory access, but the consequences vary depending on the type of resource and how it is used within the software.

Access of Uninitialized Pointer

The program accesses or uses a pointer that has not been initialized.


Products Associated with CVE-2026-3497

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-3497 are published in these products:

Canonical Ubuntu Linux
 
Red Hat Openshift
 
Red Hat Rhosemc
 
Red Hat Enterprise Linux Eus
 
Red Hat Enterprise Linux (RHEL)
 
Red Hat Rhel Aus
 
Red Hat Rhel Eus Long Life
 
Red Hat Rhel E4s
 
Red Hat Rhel Tus
 
Red Hat Rhel Eus
 
Red Hat Ai Inference Server
 
Red Hat Hummingbird
 
Red Hat Rhui
 
Red Hat Multicluster Engine
 
Red Hat Openshift Pipelines
 
Red Hat Acm
 

Affected Versions

Ubuntu openssh: Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 10.0 Extended Update Support: Red Hat Enterprise Linux 8: Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support: Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On: Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support: Red Hat Enterprise Linux 8.6 Telecommunications Update Service: Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions: Red Hat Enterprise Linux 8.8 Telecommunications Update Service: Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions: Red Hat Enterprise Linux 9: Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions: Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions: Red Hat Enterprise Linux 9.4 Extended Update Support: Red Hat Enterprise Linux 9.6 Extended Update Support: Red Hat OpenShift Container Platform 4.12: Red Hat OpenShift Container Platform 4.13: Red Hat OpenShift Container Platform 4.14: Red Hat OpenShift Container Platform 4.15: Red Hat OpenShift Container Platform 4.16: Red Hat OpenShift Container Platform 4.17: Red Hat OpenShift Container Platform 4.18: Red Hat OpenShift Container Platform 4.19: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat RHEL-8 based Middleware Containers: Red Hat AI Inference Server 3.2: Red Hat AI Inference Server 3.2: Red Hat AI Inference Server 3.2: Red Hat AI Inference Server 3.3: Red Hat AI Inference Server 3.3: Red Hat AI Inference Server 3.3: Red Hat AI Inference Server 3.3: Red Hat Hardened Images: Red Hat Update Infrastructure 5: Red Hat Update Infrastructure 5: Red Hat Multicluster Engine for Kubernetes: Red Hat OpenShift Pipelines: Red Hat Advanced Cluster Management for Kubernetes 2: Red Hat Enterprise Linux 6: Red Hat Enterprise Linux 7: Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP: Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP:

Exploit Probability

EPSS
1.96%
Percentile
77.75%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.