Vulnerability in OpenBSD OpenSSH
CVE-2026-3497
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.013 (68.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 68.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.022 · newest: 0.013 · change: -0.009
Affected products
- OpenBSD OpenSSH
- Canonical Ubuntu Linux — versions 25.10, 20.04, 22.04
- Debian Linux — versions 11.0
- Red Hat Enterprise Linux — versions 8.0, 9.0, 10.0
- Ubuntu OpenSSH — versions 1:10.0p1-5ubuntu5, 1:9.6p1-3ubuntu13, 1:8.9p1-3
Weakness classification (CWE)
References
- ubuntu.com/security/CVE-2026-3497 (Third Party Advisory, vdb-entry)
- www.openwall.com/lists/oss-security/2026/03/12/3 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-3497?
- CVE-2026-3497 is a high-severity vulnerability in OpenBSD OpenSSH, classified under Use of Uninitialized Resource. CVSS score: 7.5/10. Published 2026-03-12.
- How severe is CVE-2026-3497?
- High severity. CVSS v3 base score is 7.5 out of 10.