SB2026081454 - openEuler 20.03 LTS SP4 update for openssh

Description

This security bulletin contains information about 3 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 Neutralization of Argument Delimiters in a Command (CVE-ID: CVE-2026-59997)

CWE-ID: CWE-88 - Argument Injection or Modification

CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote user to bypass security-relevant SFTP server options.

The vulnerability exists due to improper input handling in the internal-sftp SFTP server implementation when processing long command lines. A remote privileged user can supply a command line with security-relevant options placed after the ninth argument to bypass security-relevant SFTP server options.

Only configurations using the internal-sftp SFTP server implementation are affected.

3) 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.

Remediation

Install update from vendor's website.

References

• https://www.openeuler.org/en/security/security-bulletins/detail/?id=openEuler-SA-2026-3349