CVE-2026-3497

Publication date 12 March 2026

Last updated 18 March 2026


Ubuntu priority

Description

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.

Read the notes from the security team

Status

Package Ubuntu Release Status
openssh 25.10 questing
Fixed 1:10.0p1-5ubuntu5.1
24.04 LTS noble
Fixed 1:9.6p1-3ubuntu13.15
22.04 LTS jammy
Fixed 1:8.9p1-3ubuntu0.14
20.04 LTS focal
Fixed 1:8.2p1-4ubuntu0.13+esm1
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
openssh-ssh1 25.10 questing Ignored
24.04 LTS noble Ignored
22.04 LTS jammy Ignored
20.04 LTS focal Ignored
18.04 LTS bionic Ignored

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro 30-day free trial

Notes


mdeslaur

openssh-ssh1 is only provided for compatibility with old devices that cannot be upgraded to modern protocols. We will not be providing any security support for the openssh-ssh1 package as it is insecure and should be used in trusted environments only.


ej7367

bionic and older are not affected because they use packet_disconnect() (which then calls the correct ssh_packet_disconnect() function).

References

Related Ubuntu Security Notices (USN)

Other references


Access our resources on patching vulnerabilities