Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : Net::CIDR::Lite vulnerabilities (USN-8406-1)

high Nessus Plugin ID 320398

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-8406-1 advisory.

Dave Rolsky discovered that Net::CIDR::Lite did not properly handle extraneous zero characters at the beginning of an IP address string. A remote attacker could possibly use this issue to bypass access controls that are based on IP addresses. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.
(CVE-2021-47154)

It was discovered that Net::CIDR::Lite did not properly validate the IPv6 group count when handling uncompressed IPv6 addresses. A remote attacker could possibly use this issue to bypass access controls.
(CVE-2026-40198)

It was discovered that Net::CIDR::Lite mishandled IPv4 mapped IPv6 addresses. A remote attacker could possibly use this issue to bypass access controls that are based on IP addresses. (CVE-2026-40199)

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.

Solution

Update the affected libnet-cidr-lite-perl package.

See Also

https://ubuntu.com/security/notices/USN-8406-1

Plugin Details

Severity: High

ID: 320398

File Name: ubuntu_USN-8406-1.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 6/11/2026

Updated: 6/11/2026

Supported Sensors: Continuous Assessment, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-40198

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:H/A:N

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:libnet-cidr-lite-perl, cpe:/o:canonical:ubuntu_linux:26.04:-:lts

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 6/8/2026

Vulnerability Publication Date: 3/18/2024

Reference Information

CVE: CVE-2021-47154, CVE-2026-40198, CVE-2026-40199

USN: 8406-1