{"id":"CVE-2026-19566","state":"PUBLISHED","title":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths","description":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths.\n\nThe _encode method accepts any prefix length matching `(0|[1-9][0-9]*)` and passes it to _width2bits(), which builds the mask as `'1' x ($width + 8)`, one character per bit. The _inc() method then unpacks the packed mask into a Perl array of one scalar per byte, so the prefix length alone sets the allocation size: `::/100000000` builds a 100 MB string and a 12.5 million element array. The value being tested is parsed, not just the configured ranges: contains() builds a set from its argument, and _guess_coder() tries the IPv4 coder and then the IPv6 coder, so an IPv4-only set expands an oversized IPv6 prefix length before the mixed address width check rejects it.\n\nAny caller that passes untrusted input to contains() or add() can exhaust process memory. A prefix length above 128 is also stored as a range that does not match the requested block: 2001:db8::/129 stringifies back unchanged, contains() of its own base address returns false, and removing it from a set drops the base address while the set still prints as covering it.","publishedAt":"2026-08-12T08:39:59.029Z","updatedAt":"2026-08-12T19:49:32.903Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"CPANSec","products":["RRWO Net::CIDR::Set"],"affected":[{"vendor":"RRWO","product":"Net::CIDR::Set","packageName":"Net-CIDR-Set","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.23","versionType":"custom"}],"collectionURL":"https://cpan.org/modules","programFiles":["lib/Net/CIDR/Set/IPv6.pm","lib/Net/CIDR/Set.pm"],"programRoutines":[{"name":"Net::CIDR::Set::IPv6::_encode"},{"name":"Net::CIDR::Set::IPv6::_width2bits"}],"repo":"https://github.com/robrwo/perl-Net-CIDR-Set"}],"references":["https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p","https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch","https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes","https://www.cve.org/CVERecord?id=CVE-2026-49942"],"weaknesses":["CWE-1284","CWE-789"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/19xxx/CVE-2026-19566.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-19566","state":"PUBLISHED","datePublished":"2026-08-12T08:39:59.029Z","dateUpdated":"2026-08-12T19:49:32.903Z","assignerShortName":"CPANSec","assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","dateReserved":"2026-08-11T18:53:07.963Z"},"containers":{"cna":{"title":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths","descriptions":[{"lang":"en","value":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths.\n\nThe _encode method accepts any prefix length matching `(0|[1-9][0-9]*)` and passes it to _width2bits(), which builds the mask as `'1' x ($width + 8)`, one character per bit. The _inc() method then unpacks the packed mask into a Perl array of one scalar per byte, so the prefix length alone sets the allocation size: `::/100000000` builds a 100 MB string and a 12.5 million element array. The value being tested is parsed, not just the configured ranges: contains() builds a set from its argument, and _guess_coder() tries the IPv4 coder and then the IPv6 coder, so an IPv4-only set expands an oversized IPv6 prefix length before the mixed address width check rejects it.\n\nAny caller that passes untrusted input to contains() or add() can exhaust process memory. A prefix length above 128 is also stored as a range that does not match the requested block: 2001:db8::/129 stringifies back unchanged, contains() of its own base address returns false, and removing it from a set drops the base address while the set still prints as covering it."}],"affected":[{"vendor":"RRWO","product":"Net::CIDR::Set","packageName":"Net-CIDR-Set","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"0.23","versionType":"custom"}],"collectionURL":"https://cpan.org/modules","programFiles":["lib/Net/CIDR/Set/IPv6.pm","lib/Net/CIDR/Set.pm"],"programRoutines":[{"name":"Net::CIDR::Set::IPv6::_encode"},{"name":"Net::CIDR::Set::IPv6::_width2bits"}],"repo":"https://github.com/robrwo/perl-Net-CIDR-Set"}],"references":[{"url":"https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p","tags":["vendor-advisory"]},{"url":"https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch","tags":["patch"]},{"url":"https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes","tags":["release-notes"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49942","tags":["related"]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1284","description":"CWE-1284 Improper Validation of Specified Quantity in Input","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-789","description":"CWE-789 Memory Allocation with Excessive Size Value","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"CPANSec","orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","dateUpdated":"2026-08-12T08:39:59.029Z"},"solutions":[{"lang":"en","value":"Upgrade to Net::CIDR::Set version 0.23 or later."}],"source":{"discovery":"UNKNOWN"},"workarounds":[{"lang":"en","value":"For deployments that cannot upgrade, apply the patch."}],"x_generator":{"engine":"cpansec-cna-tool 0.1"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-08-12T19:49:22.654200Z","id":"CVE-2026-19566","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-12T19:49:32.903Z"}}]}}}