USN-8928-1: OpenSSH vulnerabilities

Publication date

14 October 2026

Overview

Several security issues were fixed in OpenSSH.


Packages

  • openssh - secure shell (SSH) for secure access to remote machines

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...

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)


Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:


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