In sshd in OpenSSH before 10.6, the restrict keyword (in authorized_keys) was supposed to be applicable to tunnel forwarding but was not, a different vulnerability than CVE-2026-73283.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-3354 advisory.

    In sftp in OpenSSH before 10.6, a server can trigger directory traversal (causing files to be written to     unintended locations) during a recursive copy operation. (CVE-2026-106552)

    In sshd in OpenSSH before 10.6, credentials can incorrectly persist after failure of a     GSSAPIAuthentication authentication attempt. (CVE-2026-106553)

    In sshd in OpenSSH before 10.6, GSSAPIAuthentication authentication state can incorrectly be persisted     across authentication attempts. (CVE-2026-106555)

    In sshd and ssh in OpenSSH before 10.6, an LZ77 dictionary coder can be used even though this is     contraindicated by the arXiv 2609.07709 Crossing the Streams findings. (CVE-2026-106582)

    In ssh in OpenSSH before 10.6, a $ or \ character can occur in a command-line username, leading to     injection. (CVE-2026-106583)

    In ssh-keygen in OpenSSH before 10.6, certificates could have incorrect expiration times because of     Daylight Saving mishandling. There can be a slightly more severe effect on users in certain Antarctic     locations. (CVE-2026-106584)

    In sshd and ssh in OpenSSH before 10.6, there is no check for whether the maximum packet length is     exceeded during decompression of highly compressed data. (CVE-2026-106585)

    In sshd in OpenSSH before 10.6, the restrict keyword (in authorized_keys) was supposed to be applicable to     tunnel forwarding but was not, a different vulnerability than CVE-2026-73283. (CVE-2026-106586)

    In sshd in OpenSSH before 10.6, the value none for a configuration option is sometimes interpreted as a     filename but was intended to mean that a feature is disabled. (CVE-2026-106587)

    sftp in OpenSSH before 10.4 does not properly constrain the location of downloaded files when sftp     server:/path . is used with an attacker-controlled server. (CVE-2026-59995)

    internal-sftp in sshd in OpenSSH before 10.4 recognizes only the first 9 command-line arguments, which can     be important if a later command-line argument would have helped to ensure the intended security properties     of an SFTP connection. (CVE-2026-59997)

    sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has     no value if the server is in Windows Active Directory. (CVE-2026-59998)

    In sshd in OpenSSH before 10.4, DisableForwarding=yes was supposed to take precedence over     PermitTunnel=yes, but did not. (CVE-2026-59999)

    sshd in OpenSSH before 10.4 allows remote attackers to cause a denial of service (resource consumption     from excessive authentication attempts) because MaxAuthTries was mishandled for GSSAPIAuthentication.
    (CVE-2026-60000)

    sshd in OpenSSH before 10.4 does not always honor the minimum authentication delay. (CVE-2026-60001)

    In ssh-agent in OpenSSH before 10.5, some operations can occur remotely but were intended to occur only     locally, including operations that add tokens or use keys. This is caused by misinteraction between agent     locking and the session-bind@openssh.com extension. (CVE-2026-73281)

    In ssh in OpenSSH before 10.5, a use-after-free for realloc data can occur if a certain pair of remote-     forwarding operations are concurrent. (CVE-2026-73282)

    In sshd in OpenSSH before 10.5, the restrict keyword (in authorized_keys) was supposed to be applicable to     tunnel forwarding but was not. (CVE-2026-73283)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - In sshd in OpenSSH before 10.6, the restrict keyword (in authorized_keys) was supposed to be applicable to     tunnel forwarding but was not, a different vulnerability than CVE-2026-73283. (CVE-2026-106586)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Ubuntu 26.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8937-1 advisory.

    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)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8928-1 advisory.

    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)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The AlmaLinux 9.2 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare ALMALINUX9.2:CLSA-2026:1792197391 advisory.

  - In sftp in OpenSSH before 10.6, a server can trigger directory traversal (causing files to be written to     unintended locations) during a recursive copy operation. (CVE-2026-106552)

  - In sshd in OpenSSH before 10.6, credentials can incorrectly persist after failure of a     GSSAPIAuthentication authentication attempt. (CVE-2026-106553)

  - In sshd in OpenSSH before 10.6, GSSAPIAuthentication authentication state can incorrectly be persisted     across authentication attempts. (CVE-2026-106555)

  - In sshd and ssh in OpenSSH before 10.6, an LZ77 dictionary coder can be used even though this is     contraindicated by the arXiv 2609.07709 Crossing the Streams findings. (CVE-2026-106582)

  - In ssh in OpenSSH before 10.6, a $ or \ character can occur in a command-line username, leading to     injection. (CVE-2026-106583)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - In sshd in OpenSSH before 10.6, the restrict keyword (in authorized_keys) was supposed to be applicable to
    tunnel forwarding but was not, a different vulnerability than CVE-2026-73283. (CVE-2026-106586)

ID	Name	Product	Family	Type	Severity
374367	Amazon Linux 2023 : openssh, openssh-clients, openssh-keycat (ALAS2023-2026-3354)	Nessus	Amazon Linux Local Security Checks	Local	high
371371	Linux Distros Unpatched Vulnerability : CVE-2026-106586	Nessus	Misc.	Local	medium
367750	Ubuntu 26.10 : OpenSSH vulnerabilities (USN-8937-1)	Nessus	Ubuntu Local Security Checks	Local	high
367205	Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS : OpenSSH vulnerabilities (USN-8928-1)	Nessus	Ubuntu Local Security Checks	Local	high
366706	AlmaLinux 9.2 [TuxCare] Security Update: openssh / openssh-askpass / openssh-clients / openssh-keycat / etc Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1792197391)	Nessus	Alma Linux Local Security Checks	Local	high
473744	Echo: openssh: security update to 1:10.6p1-1	Tenable Cloud Security	Echo Local Security Checks	Local	medium
473744	Echo: openssh: security update to 1:10.6p1-1	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	medium

Detections

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CVE-2026-106586

medium

Tenable Plugins

high

medium

high

high

high

medium

medium