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CVE-2026-116270

Full vulnerability record from the local CVENow database.

Description

MIME::Words versions before 5.521 for Perl allow memory exhaustion via repeated "=?" sequences in decode_mimewords. For each "=?" that does not start a complete encoded word, decode_mimewords appends an error message containing the whole input string to $@. A boundary of 8,000 "=?" pairs (16,000 bytes) adds 8,000 copies of itself to $@, about 128 MB. From version 5.518, MIME::Parser decodes every multipart boundary this way, so a remote sender can exhaust the memory of the parsing process with one Content-Type header.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Awaiting Analysis
Source identifier
9b29abf9-4ab0-4765-b253-1875cd9b441e
Published
2026-10-28 18:17:13.470000
Last modified
2026-10-29 15:11:53
View original CVE JSON
{
  "id": "CVE-2026-116270",
  "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
  "published": "2026-10-28T18:17:13.470",
  "lastModified": "2026-10-29T15:11:53.000",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "MIME::Words versions before 5.521 for Perl allow memory exhaustion via repeated \"=?\" sequences in decode_mimewords.\n\nFor each \"=?\" that does not start a complete encoded word, decode_mimewords appends an error message containing the whole input string to $@. A boundary of 8,000 \"=?\" pairs (16,000 bytes) adds 8,000 copies of itself to $@, about 128 MB.\n\nFrom version 5.518, MIME::Parser decodes every multipart boundary this way, so a remote sender can exhaust the memory of the parsing process with one Content-Type header."
    }
  ],
  "affected": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "collectionURL": "https://cpan.org/modules",
          "packageName": "MIME-tools",
          "modules": [
            "MIME::Words"
          ],
          "programFiles": [
            "lib/MIME/Words.pm",
            "lib/MIME/Head.pm"
          ],
          "programRoutines": [
            {
              "name": "MIME::Words::decode_mimewords"
            },
            {
              "name": "MIME::Head::multipart_boundary"
            }
          ],
          "repo": "https://salsa.debian.org/dskoll/mime-tools",
          "packageURL": "pkg:cpan/MIME-tools",
          "versions": [
            {
              "version": "0",
              "lessThan": "5.521",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "weaknesses": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-407"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    }
  ]
}