Amazon Linux 2023 : valkey, valkey-devel (ALAS2023-2026-2011)

high Nessus Plugin ID 332040

Synopsis

The remote Amazon Linux 2023 host is missing a security update.

Description

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2011 advisory.

A use-after-free vulnerability exists in Valkey's TLS connection handling that can crash the server that can potentially lead to remote code execution. When TLS is enabled, the server keeps a list of connections that have leftover data waiting to be read. While working through that list, one connection being closed can cause Valkey to access memory belonging to another connection that was just freed.

This happens when an authenticated client closes a connection (for example, via CLIENT KILL) while another TLS connection still has buffered data pending. The freed memory could in principle be reclaimed and controlled via heap grooming which can lead to a potential remote code execution.

This issue only affects deployments with TLS enabled. Non-TLS deployments are not affected.
(CVE-2026-56684)

An authenticated user may use a specially crafted RESTORE command to inject a malformed RDB payload containing duplicate Pending Entry List (PEL) assignments. This triggers a use-after-free during stream consumer group deserialization or consumer deletion, potentially leading to remote code execution.

The problem exists in all versions of Valkey. (CVE-2026-63639)

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.

Solution

Run 'dnf update valkey --releasever 2023.12.20260803' or or 'dnf update --advisory ALAS2023-2026-2011 --releasever 2023.12.20260803' to update your system.

Plugin Details

Severity: High

ID: 332040

File Name: al2023_ALAS2023-2026-2011.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 8/4/2026

Updated: 8/4/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.9

Percentile: 96.83

CVSS v2

Risk Factor: High

Base Score: 9

Temporal Score: 6.7

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

CVSS Score Source: CVE-2026-63639

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

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

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

Vulnerability Information

CPE: cpe:/o:amazon:linux:2023, p-cpe:/a:amazon:linux:valkey-debuginfo, p-cpe:/a:amazon:linux:valkey-debugsource, p-cpe:/a:amazon:linux:valkey-devel, p-cpe:/a:amazon:linux:valkey

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

Exploit Ease: No known exploits are available

Patch Publication Date: 8/4/2026

Vulnerability Publication Date: 7/22/2026

Reference Information

CVE: CVE-2026-56684, CVE-2026-63639

Detections

Analytics