CVE-2026-87078 (GCVE-0-2026-87078)

Vulnerability from cvelistv5 – Published: 2026-09-22 07:19 – Updated: 2026-09-22 07:19
VLAI
Title
Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode
Summary
Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode. The XS backend allocates the scalar it returns before it validates the input, sizing the buffer at twice the input length. The scalar is released only on the success path, so each of the three croaks that reject a label leaves the scalar and its buffer allocated. Nothing bounds the label length in the to-Unicode direction, since the 63-byte DNS limit is checked only when converting to ASCII. Only the XS backend is affected. A sender who supplies invalid labels grows the process by twice the label length per rejected call, with no successful call needed.
Severity
No CVSS data available.
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
Assigner
References
Impacted products
Vendor Product Version CPE status
Affected: 2.302 , < 2.590 (custom)
Show details on NVD website
To clipboard 

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          "modules": [
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          "packageName": "Net-IDN-Encode",
          "packageURL": "pkg:cpan/Net-IDN-Encode",
          "programFiles": [
            "lib/Net/IDN/Punycode.xs"
          ],
          "programRoutines": [
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          ],
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      ],
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              "description": "CWE-401 Missing Release of Memory after Effective Lifetime",
              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
        "dateUpdated": "2026-09-22T07:19:33.195Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
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          "tags": [
            "release-notes"
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          "url": "https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/changes"
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          "value": "Upgrade to Net-IDN-Encode 2.590-TRIAL or later."
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          "lang": "en",
          "time": "2016-12-07T00:00:00.000Z",
          "value": "Version 2.302 released, introducing the defect."
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          "lang": "en",
          "time": "2026-09-17T00:00:00.000Z",
          "value": "Version 2.590-TRIAL released with fix."
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      "title": "Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode",
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    "cveId": "CVE-2026-87078",
    "datePublished": "2026-09-22T07:19:33.195Z",
    "dateReserved": "2026-09-08T19:22:20.005Z",
    "dateUpdated": "2026-09-22T07:19:33.195Z",
    "state": "PUBLISHED"
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            "value": "Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode.\n\nThe XS backend allocates the scalar it returns before it validates the input, sizing the buffer at twice the input length. The scalar is released only on the success path, so each of the three croaks that reject a label leaves the scalar and its buffer allocated. Nothing bounds the label length in the to-Unicode direction, since the 63-byte DNS limit is checked only when converting to ASCII.\n\nOnly the XS backend is affected.\n\nA sender who supplies invalid labels grows the process by twice the label length per rejected call, with no successful call needed."
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        "metrics": {},
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}



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