Vulnerability-Lookup

UBUNTU-CVE-2026-19566 (CVE-2026-19566)

Vulnerability from osv_ubuntu – Published: 2026-08-12 09:17 – Updated: 2026-08-19 11:01 – Source website

Details

Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths. The _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. Any 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.

Severity

7.5 (High)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-19566	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-19566	REPORT
	https://lists.security.metacpan.org/cve-announce/…	REPORT
	https://github.com/robrwo/perl-Net-CIDR-Set/secur…	REPORT
	https://github.com/robrwo/perl-Net-CIDR-Set/commi…	REPORT
	https://metacpan.org/release/RRWO/Net-CIDR-Set-0.…	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-49942	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnet-cidr-set-perl",
            "binary_version": "0.13-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "libnet-cidr-set-perl",
        "purl": "pkg:deb/ubuntu/libnet-cidr-set-perl@0.13-2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.13-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnet-cidr-set-perl",
            "binary_version": "0.13-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libnet-cidr-set-perl",
        "purl": "pkg:deb/ubuntu/libnet-cidr-set-perl@0.13-3?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.13-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnet-cidr-set-perl",
            "binary_version": "0.13-5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libnet-cidr-set-perl",
        "purl": "pkg:deb/ubuntu/libnet-cidr-set-perl@0.13-5?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.13-4",
        "0.13-5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnet-cidr-set-perl",
            "binary_version": "0.19-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libnet-cidr-set-perl",
        "purl": "pkg:deb/ubuntu/libnet-cidr-set-perl@0.19-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.19-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths. The _encode method accepts any prefix length matching `(0|[1-9][0-9]*)` and passes it to _width2bits(), which builds the mask as `\u00271\u0027 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. Any 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": "UBUNTU-CVE-2026-19566",
  "modified": "2026-08-19T11:01:27Z",
  "published": "2026-08-12T09:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-19566"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-19566"
    },
    {
      "type": "REPORT",
      "url": "https://lists.security.metacpan.org/cve-announce/msg/42620063/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/robrwo/perl-Net-CIDR-Set/security/advisories/GHSA-grjr-r4x5-mx4p"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/robrwo/perl-Net-CIDR-Set/commit/e16b27db676fd1ca671fbb31208a22c1b1ba9724.patch"
    },
    {
      "type": "REPORT",
      "url": "https://metacpan.org/release/RRWO/Net-CIDR-Set-0.23/changes"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-49942"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-19566"
  ]
}

CVE-2026-19566 (GCVE-0-2026-19566)

Vulnerability from cvelistv5 – Published: 2026-08-12 08:39 – Updated: 2026-08-12 19:49

Title

Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths

Summary

Net::CIDR::Set versions before 0.23 for Perl allow memory exhaustion and malformed set ranges via unbounded IPv6 prefix lengths. The _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. Any 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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-12 19:49 UTC

CWE

CWE-1284 - Improper Validation of Specified Quantity in Input
CWE-789 - Memory Allocation with Excessive Size Value

Assigner

CPANSec redhat root Scorecard

References

4 references

URL	Tags
https://github.com/robrwo/perl-Net-CIDR-Set/secur…	vendor-advisory
https://github.com/robrwo/perl-Net-CIDR-Set/commi…	patch
https://metacpan.org/release/RRWO/Net-CIDR-Set-0.…	release-notes
https://www.cve.org/CVERecord?id=CVE-2026-49942	related

Impacted products

1 product

Vendor	Product	Version
RRWO	Net::CIDR::Set	Affected: 0 , < 0.23 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-19566",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-12T19:49:22.654200Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-12T19:49:32.903Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "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 `\u00271\u0027 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": "2026-08-12T19:49:32.903Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

UBUNTU-CVE-2026-19566 (CVE-2026-19566)

CVE-2026-19566 (GCVE-0-2026-19566)

Tags

Sightings

Nomenclature

Related by attack behaviour