Bug 2447085 (CVE-2026-3497)

Summary: CVE-2026-3497 openssh: OpenSSH GSSAPI: Information disclosure or denial of service due to uninitialized variables
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: adudiak, kshier, stcannon, teagle, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the OpenSSH GSSAPI (Generic Security Service Application Program Interface) delta patches, as included in various Linux distributions. A remote attacker could exploit this by sending an unexpected GSSAPI message type during the key exchange process. This occurs because the `sshpkt_disconnect()` function, when called on an error, does not properly terminate the process, leading to the continued execution of the program with uninitialized connection variables. Accessing these uninitialized variables can lead to undefined behavior, potentially resulting in information disclosure or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2447289, 2447290    
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Description OSIDB Bzimport 2026-03-12 19:02:00 UTC 
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.