{"api_version":"1","generated_at":"2026-08-12T11:39:47+00:00","cve":"CVE-2026-19566","urls":{"html":"https://cve.report/CVE-2026-19566","api":"https://cve.report/api/cve/CVE-2026-19566.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-19566","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-19566"},"summary":{"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.","state":"PUBLISHED","assigner":"CPANSec","published_at":"2026-08-12 09:17:29","updated_at":"2026-08-12 09:17:29"},"problem_types":["CWE-789","CWE-1284","CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input","CWE-789 CWE-789 Memory Allocation with Excessive Size Value"],"metrics":[],"references":[{"url":"https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p","name":"https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes","name":"https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch","name":"https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49942","name":"https://www.cve.org/CVERecord?id=CVE-2026-49942","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-19566","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-19566","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"RRWO","product":"Net::CIDR::Set","version":"affected 0.23 custom","platforms":[]}],"timeline":[],"solutions":[{"source":"CNA","title":"","value":"Upgrade to Net::CIDR::Set version 0.23 or later.","time":"","lang":"en"}],"workarounds":[{"source":"CNA","title":"","value":"For deployments that cannot upgrade, apply the patch.","time":"","lang":"en"}],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"collectionURL":"https://cpan.org/modules","defaultStatus":"unaffected","packageName":"Net-CIDR-Set","product":"Net::CIDR::Set","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","vendor":"RRWO","versions":[{"lessThan":"0.23","status":"affected","version":"0","versionType":"custom"}]}],"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."}],"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":{"dateUpdated":"2026-08-12T08:39:59.029Z","orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","shortName":"CPANSec"},"references":[{"tags":["vendor-advisory"],"url":"https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p"},{"tags":["patch"],"url":"https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch"},{"tags":["release-notes"],"url":"https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes"},{"tags":["related"],"url":"https://www.cve.org/CVERecord?id=CVE-2026-49942"}],"solutions":[{"lang":"en","value":"Upgrade to Net::CIDR::Set version 0.23 or later."}],"source":{"discovery":"UNKNOWN"},"title":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths","workarounds":[{"lang":"en","value":"For deployments that cannot upgrade, apply the patch."}],"x_generator":{"engine":"cpansec-cna-tool 0.1"}}},"cveMetadata":{"assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","assignerShortName":"CPANSec","cveId":"CVE-2026-19566","datePublished":"2026-08-12T08:39:59.029Z","dateReserved":"2026-08-11T18:53:07.963Z","dateUpdated":"2026-08-12T08:39:59.029Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-12 09:17:29","lastModifiedDate":"2026-08-12 09:17:29","problem_types":["CWE-789","CWE-1284","CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input","CWE-789 CWE-789 Memory Allocation with Excessive Size Value"],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"19566","Ordinal":"1","Title":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaus","CVE":"CVE-2026-19566","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"19566","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Net::CIDR::Set versions before 0.23 for Perl allow memory exhaus"}]}}}