QSN-8928-1: OpenSSH vulnerabilities
2026-10-14

Summary:
Several security issues were fixed in OpenSSH.

Details:
It was discovered that OpenSSH's sftp client incorrectly handled paths
returned by the server during a recursive copy operation. A remote
attacker controlling the server could possibly use this issue to write
files to unintended locations. (CVE-2026-106552)

It was discovered that OpenSSH's sshd server incorrectly handled
GSSAPIAuthentication state across authentication attempts. An attacker
could possibly use this issue to obtain credentials from a previous
failed authentication attempt. (CVE-2026-106553, CVE-2026-106555)

It was discovered that OpenSSH incorrectly used an LZ77 dictionary coder
during compression. An attacker could possibly use this issue to obtain
sensitive information. (CVE-2026-106582)

It was discovered that OpenSSH's ssh client incorrectly allowed special
characters in command-line usernames. An attacker could possibly use this
issue to inject arbitrary commands via specially crafted usernames.
(CVE-2026-106583)

It was discovered that OpenSSH's ssh-keygen incorrectly handled Daylight
Saving Time when converting dates. An attacker could possibly use this
issue to cause certificates to have incorrect expiration times.
(CVE-2026-106584)

It was discovered that OpenSSH did not check whether the maximum packet
length was exceeded during decompression. A remote attacker could possibly
use this issue to cause a denial of service. (CVE-2026-106585)

It was discovered that OpenSSH's sshd server incorrectly applied the
restrict keyword from authorized_keys to tunnel forwarding requests. A
local attacker with an authorized key could possibly use this issue to
bypass intended tunnel forwarding restrictions. (CVE-2026-106586)

It was discovered that OpenSSH's sshd server incorrectly handled certain
configuration options that accept a "none" value. An attacker could
possibly use this issue to cause OpenSSH to behave unexpectedly.
(CVE-2026-106587)

Affected QuantaStor releases:
  6.9.1.001 jammy: openssh-client 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.9.1.001 jammy: openssh-server 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.9.1.001 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.9.0.464 jammy: openssh-client 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.9.0.464 jammy: openssh-server 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.9.0.464 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.18 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.6.015 jammy: openssh-client 1:8.9p1-3ubuntu0.17 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.6.015 jammy: openssh-server 1:8.9p1-3ubuntu0.17 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.6.015 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.17 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.5.018 jammy: openssh-client 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.5.018 jammy: openssh-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.5.018 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.4.038 jammy: openssh-client 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.4.038 jammy: openssh-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.4.038 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.3.018 jammy: openssh-client 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.3.018 jammy: openssh-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.3.018 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.2.002 jammy: openssh-client 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.2.002 jammy: openssh-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.2.002 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.1.007 jammy: openssh-client 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.1.007 jammy: openssh-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.1.007 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.16 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.0.205 jammy: openssh-client 1:8.9p1-3ubuntu0.15 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.0.205 jammy: openssh-server 1:8.9p1-3ubuntu0.15 (fixed in 1:8.9p1-3ubuntu0.18)
  6.8.0.205 jammy: openssh-sftp-server 1:8.9p1-3ubuntu0.15 (fixed in 1:8.9p1-3ubuntu0.18)

CVEs: CVE-2026-106552, CVE-2026-106553, CVE-2026-106585, CVE-2026-106583, CVE-2026-106584, CVE-2026-106586, CVE-2026-106587, CVE-2026-106555, CVE-2026-106582

References:
  https://ubuntu.com/security/notices/USN-8928-1