{"id":"CVE-2026-40198","summary":"Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass","details":"Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass.\n\n_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).\n\nThe 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.\n\nExample:\n\n  my $cidr = Net::CIDR::Lite-\u003enew(\"::/8\");\n  $cidr-\u003efind(\"1:2:3\");  # invalid input, incorrectly returns true\n\nThis is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module.\n\nSee also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses.","modified":"2026-05-01T04:33:33.129525Z","published":"2026-04-10T21:42:06.835Z","database_specific":{"cwe_ids":["CWE-1286"],"cna_assigner":"CPANSec","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40198.json"},"references":[{"type":"WEB","url":"https://cpan.org/modules"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40198.json"},{"type":"PACKAGE","url":"https://github.com/stigtsp/Net-CIDR-Lite"},{"type":"FIX","url":"https://github.com/stigtsp/Net-CIDR-Lite/commit/25d65f85dbe4885959a10471725ec9d250a589c3.patch"},{"type":"ADVISORY","url":"https://metacpan.org/release/STIGTSP/Net-CIDR-Lite-0.23/changes"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40198"},{"type":"WEB","url":"https://www.cve.org/CVERecord?id=CVE-2026-40199"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/stigtsp/net-cidr-lite","events":[{"introduced":"0"},{"fixed":"9a0759afb56ec1a442d7cbb657ac07f6f3c29b17"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"fixed":"0.23"}]}}],"versions":["0.21","0.22"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-40198.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}