{"id":"CVE-2026-116272","title":"MIME::Field::ParamVal versions before 5.521 for Perl do not flag a duplicate boundary parameter whose name contains a nested comment","summary":"MIME::Field::ParamVal versions before 5.521 for Perl do not flag a duplicate boundary parameter whose name contains a nested comment.\n\nA parameter written boundary((c))=\"A\" or boundary(\\))=\"A\" is stored under that literal name rather tha…","severity":"none","cwe":["CWE-436"],"product":"MIME-tools","affected":["MIME-tools < 5.521"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T17:34:25.862Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-116272","references":[{"url":"https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T18:15:46.380Z","slug":"CVE-2026-116272","body":"## Overview\n\nMIME::Field::ParamVal versions before 5.521 for Perl do not flag a duplicate boundary parameter whose name contains a nested comment.\n\nA parameter written boundary((c))=\"A\" or boundary(\\))=\"A\" is stored under that literal name rather than as boundary. A second boundary parameter is then not reported as a duplicate, and MIME::Parser splits the message on it.\n\nReaders that skip comments as RFC 5322 allows take the first boundary instead. A remote sender can hide an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it.\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":[]}