Improper access control in OpenSSH - CVE-2026-35414

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Main Vulnerability Database Vulnerabilities #VU128474

Improper access control in OpenSSH - CVE-2026-35414

Published: April 29, 2026


Vulnerability identifier: #VU128474
CSH Severity: Low
CVSS v4: 7.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-35414
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to bypass principal restrictions in certificate-based authentication.

The vulnerability exists due to improper access control in sshd(8) when matching an authorized_keys principals="" option against a list of principals in a certificate. A remote user can present a specially crafted certificate to bypass principal restrictions in certificate-based authentication.

This condition only affects user-trusted CA keys in authorized_keys and requires multiple principals to be listed, including a certificate principal containing a comma character.


Affected software

OpenSSH
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server 11
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro for Rancher
SUSE Linux Enterprise Micro
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Anolis OS
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Desktop Applications Module
Basesystem Module
openSUSE Leap
Ubuntu
openEuler
Fedora
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
pam_ssh_agent_auth
openssh-helpers
openssh-fips
openssh
openssh-askpass-gnome
openssh-cavs
openssh-askpass-gnome-debuginfo
openssh-debugsource
openssh-debuginfo
openssh (Ubuntu package)
openssh-helpers-debuginfo
openssh (Red Hat package)
openssh-askpass
openssh-server
openssh-ldap
openssh-keycat
openssh-clients
openssh8.4-server-debuginfo
openssh8.4-clients-debuginfo
openssh8.4-common
openssh8.4-helpers
openssh8.4-helpers-debuginfo
openssh8.4-server
openssh8.4
openssh8.4-clients
openssh8.4-common-debuginfo
openssh8.4-fips
openssh8.4-debugsource
openssh-common
openssh-askpass-gnome-debugsource
openssh-cavs-debuginfo
openssh-clients-debuginfo
openssh-server-debuginfo
openssh-common-debuginfo
openssh-sk-dummy
openssh-doc
openssh-help
openssh-server-config-disallow-rootlogin

How to mitigate CVE-2026-35414

Install security update from vendor's website.

OpenSSH - update to 10.3p1
pam_ssh_agent_auth - update to 0.10.3-7.29.0.1
pam_ssh_agent_auth - update to 0.10.4-5.13
openssh-helpers - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-fips - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-askpass-gnome - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-cavs - addressed in versions 6.6p1-36.31.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-askpass-gnome-debuginfo - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-debugsource - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-debuginfo - addressed in versions 6.6p1-36.31.1, 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh (Ubuntu package) - addressed in versions 1:7.2p2-4ubuntu2.10+esm9, 1:8.9p1-3ubuntu0.15, 1:9.6p1-3ubuntu13.16, 1:10.0p1-5ubuntu5.4, 1:10.2p1-2ubuntu3.2
openssh-helpers-debuginfo - addressed in versions 7.2p2-81.37.1, 7.2p2-81.40.1, 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh (Red Hat package) - addressed in versions 8.0p1-7.el8_4.2, 8.0p1-15.el8_6.5, 8.0p1-20.el8_8.4, 8.0p1-29.el8_10, 8.7p1-30.el9_2.11, 8.7p1-45.el9_6.3, 8.7p1-49.el9_7, 9.9p1-7.el10_0.3, 9.9p1-14.el10_1
openssh-askpass - addressed in versions 8.0p1-29.0.1, 9.6p1-5
openssh - addressed in versions 8.0p1-29.0.1, 9.6p1-5
openssh-server - addressed in versions 8.0p1-29.0.1, 9.6p1-5
openssh-ldap - update to 8.0p1-29.0.1
openssh-keycat - addressed in versions 8.0p1-29.0.1, 9.6p1-5
openssh-clients - addressed in versions 8.0p1-29.0.1, 9.6p1-5
openssh-cavs - update to 8.0p1-29.0.1
openssh8.4-server-debuginfo - update to 8.4p1-8.24.1
openssh8.4-clients-debuginfo - update to 8.4p1-8.24.1
openssh8.4-common - update to 8.4p1-8.24.1
openssh8.4-helpers - update to 8.4p1-8.24.1
openssh8.4-helpers-debuginfo - update to 8.4p1-8.24.1
openssh8.4-server - update to 8.4p1-8.24.1
openssh8.4 - update to 8.4p1-8.24.1
openssh8.4-clients - update to 8.4p1-8.24.1
openssh8.4-common-debuginfo - update to 8.4p1-8.24.1
openssh8.4-fips - update to 8.4p1-8.24.1
openssh8.4-debugsource - update to 8.4p1-8.24.1
openssh-common - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-askpass-gnome-debugsource - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-cavs-debuginfo - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-clients-debuginfo - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-server-debuginfo - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-common-debuginfo - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-clients - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-server - addressed in versions 8.4p1-150300.3.60.1, 8.4p1-150300.3.65.1, 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh-sk-dummy - update to 9.6p1-5
openssh-doc - update to 9.6p1-5
openssh-clients - update to 9.6p1-13
openssh - update to 9.6p1-13
openssh-server - update to 9.6p1-13
openssh-debuginfo - update to 9.6p1-13
openssh-askpass - update to 9.6p1-13
openssh-debugsource - update to 9.6p1-13
openssh-help - update to 9.6p1-13
openssh-keycat - update to 9.6p1-13
openssh-server-config-disallow-rootlogin - addressed in versions 9.6p1-150600.6.37.1, 9.6p1-150600.6.42.1
openssh - addressed in versions 10.0p1-9.fc43, 10.2p1-8.fc44

External References

Related Security Bulletins