CVE-2026-87081 (GCVE-0-2026-87081)

Vulnerability from cvelistv5 – Published: 2026-09-22 07:25 – Updated: 2026-09-22 07:25
VLAI
Title
Net::IDN::UTS46 versions before 2.590 for Perl allow CPU exhaustion via quadratic punycode encoding of an overlong label before the length check in to_ascii
Summary
Net::IDN::UTS46 versions before 2.590 for Perl allow CPU exhaustion via quadratic punycode encoding of an overlong label before the length check in to_ascii. to_ascii punycode encodes each label and only then applies the 63-byte DNS limit. encode_punycode in both backends follows the sample implementation in RFC 3492, whose outer loop runs once per distinct non-ASCII code point and scans the whole input each round, so a label of distinct non-ASCII characters costs the square of its length before the limit rejects it. Every ASCII conversion in the distribution, including domain_to_ascii and email_to_ascii, goes through to_ascii.
Severity
No CVSS data available.
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
Impacted products
Vendor Product Version CPE status
Affected: 0 , < 2.590 (custom)
Show details on NVD website
To clipboard 

{
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        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "modules": [
            "Net::IDN::UTS46"
          ],
          "packageName": "Net-IDN-Encode",
          "packageURL": "pkg:cpan/Net-IDN-Encode",
          "programFiles": [
            "lib/Net/IDN/UTS46.pm"
          ],
          "programRoutines": [
            {
              "name": "Net::IDN::UTS46::to_ascii"
            },
            {
              "name": "Net::IDN::UTS46::uts46_to_ascii"
            }
          ],
          "repo": "https://github.com/robrwo/Net-IDN-Encode",
          "versions": [
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        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-407",
              "description": "CWE-407 Inefficient Algorithmic Complexity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-22T07:25:22.090Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes"
        },
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          "tags": [
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          "url": "https://github.com/robrwo/Net-IDN-Encode/commit/5ac3315131264670efcd3a29857b651506dfee8e.patch"
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      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to Net-IDN-Encode 2.590-TRIAL or later."
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Net::IDN::UTS46 versions before 2.590 for Perl allow CPU exhaustion via quadratic punycode encoding of an overlong label before the length check in to_ascii",
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    "assignerShortName": "CPANSec",
    "cveId": "CVE-2026-87081",
    "datePublished": "2026-09-22T07:25:22.090Z",
    "dateReserved": "2026-09-08T19:22:20.005Z",
    "dateUpdated": "2026-09-22T07:25:22.090Z",
    "state": "PUBLISHED"
  },
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  "vulnerability-lookup:meta": {
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          }
        ],
        "id": "CVE-2026-87081",
        "lastModified": "2026-09-22T08:16:40.863",
        "metrics": {},
        "published": "2026-09-22T08:16:40.863",
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            "type": "Secondary"
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    }
  }
}



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