Ubuntu alert USN-8110-1 (libnet-cidr-perl)

From:
             
 
noreply+usn-bot@canonical.com
To:
             
 
ubuntu-security-announce@lists.ubuntu.com
Subject:
             
 
[USN-8110-1] Net-CIDR vulnerability
Date:
             
 
Mon, 23 Mar 2026 08:56:25 +0000
Message-ID:
             
 
<E1w4b5F-0000x3-54@lists.ubuntu.com>
==========================================================================
Ubuntu Security Notice USN-8110-1
March 18, 2026

libnet-cidr-perl vulnerability
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 24.04 LTS
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Net-CIDR could allow unintended access to network services.

Software Description:
- libnet-cidr-perl: module for merging IPv4 or IPv6 CIDR address ranges

Details:

Dave Rolsky discovered that Net-CIDR did not properly sanitize IP
addresses. An attacker could possibly use this to bypass IP-based
restrictions.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 24.04 LTS
  libnet-cidr-perl                0.21-2ubuntu0.2

Ubuntu 22.04 LTS
  libnet-cidr-perl                0.21-1ubuntu0.2

Ubuntu 20.04 LTS
  libnet-cidr-perl                0.20-1ubuntu0.1~esm2
                                  Available with Ubuntu Pro

Ubuntu 18.04 LTS
  libnet-cidr-perl                0.18-1ubuntu0.1~esm2
                                  Available with Ubuntu Pro

Ubuntu 16.04 LTS
  libnet-cidr-perl                0.17-1ubuntu0.16.04.1~esm2
                                  Available with Ubuntu Pro

Ubuntu 14.04 LTS
  libnet-cidr-perl                0.17-1ubuntu0.14.04.1~esm2
                                  Available with Ubuntu Pro

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-8110-1
  CVE-2021-4456

Package Information:
  https://launchpad.net/ubuntu/+source/libnet-cidr-perl/0.2...
  https://launchpad.net/ubuntu/+source/libnet-cidr-perl/0.2...


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