CVE-2026-40198 (GCVE-0-2026-40198)

Vulnerability from cvelistv5 – Published: 2026-04-10 21:42 – Updated: 2026-04-13 14:41
VLAI
Title
Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass
Summary
Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass. _pack_ipv6() does not check that uncompressed IPv6 addresses (without ::) have exactly 8 hex groups. Inputs like "abcd", "1:2:3", or "1:2:3:4:5:6:7" are accepted and produce packed values of wrong length (3, 7, or 15 bytes instead of 17). The packed values are used internally for mask and comparison operations. find() and bin_find() use Perl string comparison (lt/gt) on these values, and comparing strings of different lengths gives wrong results. This can cause find() to incorrectly report an address as inside or outside a range. Example: my $cidr = Net::CIDR::Lite->new("::/8"); $cidr->find("1:2:3"); # invalid input, incorrectly returns true This is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module. See also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-13 14:41 UTC
CWE
  • CWE-1286 - Improper Validation of Syntactic Correctness of Input
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 63/100 over 317 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
STIGTSP Net::CIDR::Lite Affected: 0 , < 0.23 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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