Detections
Analytics

Azure Linux 3.0 Security Update: openssh (CVE-2025-26466)

medium Nessus Plugin ID 295897

Synopsis

The remote Azure Linux host is missing one or more security updates.

Description

The version of openssh installed on the remote Azure Linux 3.0 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the CVE-2025-26466 advisory.

 - A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client May keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server May become unavailable, resulting in a denial of service attack. (CVE-2025-26466)

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

Solution

Update the affected packages.

See Also

https://nvd.nist.gov/vuln/detail/CVE-2025-26466

Plugin Details

Severity: Medium

ID: 295897

File Name: azure_linux_CVE-2025-26466.nasl

Version: 1.1

Type: local

Published: 1/22/2026

Updated: 1/22/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4.2

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2025-26466

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.3

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:microsoft:azure_linux:openssh-clients, p-cpe:/a:microsoft:azure_linux:pam_ssh_agent_auth, x-cpe:/o:microsoft:azure_linux, p-cpe:/a:microsoft:azure_linux:openssh-debuginfo, p-cpe:/a:microsoft:azure_linux:openssh, p-cpe:/a:microsoft:azure_linux:openssh-server

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/AzureLinux/release, Host/AzureLinux/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 3/11/2025

Vulnerability Publication Date: 12/12/2023

Reference Information

CVE: CVE-2025-26466

IAVA: 2025-A-0126-S