CVE-2026-45191
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk22th percentile - higher than 22% of all known CVEs
Summary
In Net::CIDR::Lite for Perl (versions before 0.24), extraneous zero characters in CIDR mask values are not properly considered, which may allow IP ACL bypass. Masks like "/00" and "/01" pass validation and parse to the same prefix as their unpadded value.
Risk Assessment
An attacker can bypass CIDR-based ACL rules, gaining unauthorized access to network resources.
Recommendation
Update Net::CIDR::Lite to version 0.24 or later.
Other vulnerabilities in Net::CIDR::Lite
See all- CVE-2026-45190Medium
Net::CIDR::Lite for Perl before version 0.24 does not properly validate IP address and CIDR mask inputs, which may allow IP ACL bypass. Inputs with trailing newline or non-ASCII digit characters pass validators but are re-encoded to a different address, causing incorrect matches.
- CVE-2026-40199Medium
Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass. _pack_ipv6() includes the sentinel byte from _pack_ipv4(), producing an 18-byte value instead of 17 bytes, causing incorrect results in mask operations and in find()/bin_find().
Original NVD description (English source)
Net::CIDR::Lite versions before 0.24 for Perl does not properly consider extraneous zero characters in CIDR mask values, which may allow IP ACL bypass. Mask forms like "/00" and "/01" pass validation and parse to the same prefix as their unpadded value. See also CVE-2026-45190.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS