Ubuntu Security Notices USN-8453-1 USN-8453-1: Net::CIDR::Lite vulnerabilities Publication date 18 June 2026 Overview Several security issues were fixed in Net::CIDR::Lite. Releases 26.04 LTS 25.10 24.04 LTS 22.04 LTS 20.04 LTS 18.04 LTS 16.04 LTS Open side navigation Close side navigation Packages Details Update instructions References Packages libnet-cidr-lite-perl - module for merging IPv4 or IPv6 CIDR address ranges Details It was discovered that Net::CIDR::Lite incorrectly validated IP address and CIDR mask inputs. An attacker could possibly use this issue to bypass IP access control lists. ( CVE-2026-45190 ) It was discovered that Net::CIDR::Lite incorrectly handled extraneous zero characters in CIDR mask values. An attacker could possibly use this issue to bypass IP access control lists. ( CVE-2026-45191 ) It was discovered that Net::CIDR::Lite incorrectly validated IP address and CIDR mask inputs. An attacker could possibly use this issue to bypass IP access control lists. ( CVE-2026-45190 ) It was discovered that Net::CIDR::Lite incorrectly handled extraneous zero characters in CIDR mask values. An attacker could possibly use this issue to bypass IP access control lists. ( CVE-2026-45191 ) Update instructions In general, a standard system update will make all the necessary changes. Learn more about how to get the fixes. The problem can be corrected by updating your system to the following package versions: Ubuntu Release Package Version 26.04 LTS resolute libnet-cidr-lite-perl – 0.22-2ubuntu0.26.04.2 25.10 questing libnet-cidr-lite-perl – 0.22-2ubuntu0.25.10.2 24.04 LTS noble libnet-cidr-lite-perl – 0.22-2ubuntu0.24.04.2 22.04 LTS jammy libnet-cidr-lite-perl – 0.22-1ubuntu0.2 20.04 LTS focal libnet-cidr-lite-perl – 0.21-2ubuntu0.1+esm2 Ubuntu Pro Fix available with Ubuntu Pro . 18.04 LTS bionic libnet-cidr-lite-perl – 0.21-1ubuntu0.18.04.1~esm2 Ubuntu Pro Fix available with Ubuntu Pro . 16.04 LTS xenial libnet-cidr-lite-perl – 0.21-1ubuntu0.16.04.1~esm2 Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. Get Ubuntu Pro References CVE-2026-45191 CVE-2026-45190 CVE-2026-45191 CVE-2026-45190