SB20260921164 - Red Hat Enterprise Linux 10 update for openssh
Published: September 21, 2026 Updated: September 30, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Path traversal (CVE-ID: CVE-2026-59995)
CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to write files to an unexpected location.
The vulnerability exists due to improper path restriction in sftp(1) when downloading files on the command line using a remote path and a local dot destination. A remote attacker can operate a malicious server to write files to an unexpected location.
2) Improper access control (CVE-ID: CVE-2026-59999)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to enable tunneling despite forwarding restrictions.
The vulnerability exists due to improper access control in sshd(8) when DisableForwarding=yes and PermitTunnel=yes are configured together. A remote privileged user can use tunneling despite forwarding restrictions to enable tunneling despite forwarding restrictions.
Exploitation requires configurations where PermitTunnel is enabled.
3) Improper access control (CVE-ID: CVE-2026-73283)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to bypass forwarding restrictions.
The vulnerability exists due to improper access control in sshd authorized_keys restrict keyword enforcement when handling tunnel forwarding. A remote user can use tunnel forwarding despite intended restrictions to bypass forwarding restrictions.
Tunnel forwarding is administratively disabled by default.
4) Improper access control (CVE-ID: CVE-2026-73281)
CWE-ID: CWE-284 - Improper Access Control
CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to bypass intended local-only restrictions on agent operations.
The vulnerability exists due to improper access control in ssh-agent session binding handling when processing forwarded agent binding requests while the agent is locked. A remote user can send crafted requests through a forwarded agent to bypass intended local-only restrictions on agent operations.
This may permit adding PKCS#11 tokens and using keys with destination restrictions through a forwarded agent.
5) Use-after-free (CVE-ID: CVE-2026-73282)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to use-after-free in the ssh client remote forwarding handling when a remote forwarding is added via the local session multiplexing socket while a remote forwarding open request is pending with the server. A remote user can trigger this race condition to cause a denial of service.
Exploitation requires access to the local session multiplexing socket while a remote forwarding open request is pending.
Remediation
Install update from vendor's website.