SB2026092042 - openEuler 24.03 LTS SP3 update for openssh

Description

This security bulletin contains information about 2 vulnerabilities.

1) 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.

2) 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.

Remediation

Install update from vendor's website.

References

• https://www.openeuler.org/en/security/security-bulletins/detail/?id=openEuler-SA-2026-3926