AlmaLinux 9.2 [TuxCare] Security Update: openssh / openssh-askpass / openssh-clients / openssh-keycat / etc (ALMALINUX9.2:CLSA-2026:1783694178)

medium Nessus Plugin ID 351740

Synopsis

The AlmaLinux host is missing one or more security updates.

Description

The AlmaLinux 9.2 host has packages installed that are affected by a vulnerability as referenced in the TuxCare ALMALINUX9.2:CLSA-2026:1783694178 advisory.

- A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie- Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS). (CVE-2026-55653)

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 based on the guidance in TuxCare advisory ALMALINUX9.2:CLSA-2026:1783694178.

See Also

https://cve.tuxcare.com/els/releases/CLSA-2026:1783694178

http://www.nessus.org/u?0df4ed48

Plugin Details

Severity: Medium

ID: 351740

File Name: tuxcare_alma_linux_9.2_CLSA-2026-1783694178.nasl

Version: 1.1

Type: Local

Published: 9/30/2026

Updated: 9/30/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.74

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.1

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

CVSS Score Source: CVE-2026-55653

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.9

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

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

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/AlmaLinux/release, Host/AlmaLinux/rpm-list, Host/OS/extended-third-party

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 7/10/2026

Vulnerability Publication Date: 6/23/2026

Reference Information

CVE: CVE-2026-55653

CLSA: 2026:1783694178