Azure Linux 3.0 Security Update: CBL-Mariner Releases (CVE-2026-40164)

high Nessus Plugin ID 307505

Synopsis

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

Description

The version of CBL-Mariner Releases 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-2026-40164 advisory.

- jq is a command-line JSON processor. Before commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784, jq used MurmurHash3 with a hardcoded, publicly visible seed (0x432A9843) for all JSON object hash table operations, which allowed an attacker to precompute key collisions offline. By supplying a crafted JSON object (~100 KB) where all keys hashed to the same bucket, hash table lookups degraded from O(1) to O(n), turning any jq expression into an O(n) operation and causing significant CPU exhaustion. This affected common jq use cases such as CI/CD pipelines, web services, and data processing scripts, and was far more practical to exploit than existing heap overflow issues since it required only a small payload. This issue has been patched in commit 0c7d133c3c7e37c00b6d46b658a02244fdd3c784. (CVE-2026-40164)

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.

Plugin Details

Severity: High

ID: 307505

File Name: azure_linux_CVE-2026-40164.nasl

Version: 1.1

Type: Local

Published: 4/19/2026

Updated: 4/19/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-40164

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: p-cpe:/a:microsoft:azure_linux:jq, x-cpe:/o:microsoft:azure_linux

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/14/2026

Vulnerability Publication Date: 4/13/2026

Reference Information

CVE: CVE-2026-40164