{"id":"CVE-2026-116270","title":"MIME::Words versions before 5.521 for Perl allow memory exhaustion via repeated \"=?\" sequences in decode_mimewords","summary":"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 whol…","severity":"none","cwe":["CWE-407"],"product":"MIME-tools","affected":["MIME-tools < 5.521"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T17:33:48.187Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-116270","references":[{"url":"https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T18:15:46.381Z","slug":"CVE-2026-116270","body":"## Overview\n\nMIME::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.\n\n## Affected\n\n- `MIME-tools < 5.521`\n\n## Remediation\n\nUpgrade to MIME-tools 5.521 or later.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}