{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.23"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "a56d59cdfbe14cb3ae051acbd1ea12f6734ff130"
            },
            {
              "fixed": "e16b27db676fd1ca671fbb31208a22c1b1ba9724"
            }
          ],
          "repo": "https://github.com/robrwo/perl-net-cidr-set",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-grjr-r4x5-mx4p"
  ],
  "database_specific": {
    "cna_assigner": "CPANSec",
    "cwe_ids": [
      "CWE-1284",
      "CWE-789"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19566.json"
  },
  "details": "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.",
  "id": "CVE-2026-19566",
  "modified": "2026-08-15T04:06:51.265217167Z",
  "published": "2026-08-12T08:39:59.029Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://cpan.org/modules"
    },
    {
      "type": "WEB",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-49942"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19566.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p"
    },
    {
      "type": "ADVISORY",
      "url": "https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19566"
    },
    {
      "type": "FIX",
      "url": "https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/robrwo/perl-Net-CIDR-Set"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths"
}