Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass
概要
Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv4 mapped IPv6 addresses, which may allow IP ACL bypass
原文の説明
取得元が公開している説明をそのまま載せています (多くは英語)。
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() when building the packed representation of IPv4 mapped addresses like ::ffff:192.168.1.1. This produces an 18 byte value instead of 17 bytes, misaligning the IPv4 part of the address.
The wrong length causes incorrect results in mask operations (bitwise AND truncates to the shorter operand) and in find() / bin_find() which use Perl string comparison (lt/gt). This can cause find() to incorrectly match or miss addresses.
Example:
my $cidr = Net::CIDR::Lite->new("::ffff:192.168.1.0/120");
$cidr->find("::ffff:192.168.2.0"); # incorrectly returns true
This is triggered by valid RFC 4291 IPv4 mapped addresses (::ffff:x.x.x.x).
See also CVE-2026-40198, a related issue in the same function affecting malformed IPv6 addresses.
ディストリビューション別の修正状況
各ディストリビューションが公開している、この CVE の修正パッケージ
- Alpine Linux ALPINE-CVE-2026-40199 perl-net-cidr-lite 修正版: 0.23-r0
- Debian DEBIAN-CVE-2026-40199 libnet-cidr-lite-perl
- Ubuntu UBUNTU-CVE-2026-40199 libnet-cidr-lite-perl
参照URL
- advisory github.com
- advisory metacpan.org
- advisory nvd.nist.gov
- package github.com
- patch github.com
- web cpan.org
- web cve.org