CVE-2026-59998

Publication date 8 July 2026

Last updated 13 July 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

4.8 · Medium

Score breakdown

Description

sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no value if the server is in Windows Active Directory.

Read the notes from the security team

Status

Package Ubuntu Release Status
openssh 26.04 LTS resolute
Fixed 1:10.2p1-2ubuntu3.4
25.10 questing Ignored end of life, was needs-triage
24.04 LTS noble
Fixed 1:9.6p1-3ubuntu13.18
22.04 LTS jammy
Fixed 1:8.9p1-3ubuntu0.16
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation
openssh-ssh1 26.04 LTS resolute Ignored
25.10 questing Ignored
24.04 LTS noble Ignored
22.04 LTS jammy Ignored
20.04 LTS focal Ignored
18.04 LTS bionic Ignored

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. The commit below is purely a documentation change.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
openssh

Severity score breakdown

CVSS version: CVSS v3.0

Base score 4.8 · Medium

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

Related Ubuntu Security Notices (USN)

Other references

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