{"id":"CVE-2026-116265","published":"2026-10-28T18:17:12.910","lastModified":"2026-10-28T18:17:12.910","description":"MIME::Field::ParamVal versions before 5.521 for Perl do not flag an ambiguous multipart boundary written as RFC 2231 continuations.\n\nThe boundary ambiguity checks look only at a plain boundary= parameter, and a boundary split into RFC 2231 sections (boundary*0=, boundary*1= and so on) is joined after they have run. A repeated section number is concatenated rather than reported as a duplicate. From version 5.518, an encoded word or trailing whitespace in such a boundary also goes unflagged, although multipart_boundary() decodes or strips it.\n\nA remote sender can make MIME::Parser split a message on a different boundary than other mail readers, hiding an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-436"],"vendors":[],"products":[],"references":[{"url":"https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}