{"id":"CVE-2026-116269","title":"MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename","summary":"MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename.\n\nA parameter such as filename*=utf-8'en-US'payload.exe is converted to an encoded word with…","severity":"none","cwe":["CWE-436"],"product":"MIME-tools","affected":["MIME-tools < 5.521"],"published":"2026-10-28","updated":"2026-10-28","sourceUpdated":"2026-10-28T17:33:22.332Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-116269","references":[{"url":"https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"}],"tags":["cve.org"],"ingestedAt":"2026-10-28T18:15:46.382Z","slug":"CVE-2026-116269","body":"## Overview\n\nMIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename.\n\nA parameter such as filename*=utf-8'en-US'payload.exe is converted to an encoded word with the language tag appended to the charset. The decoder strips the language suffix only when it is a single word, so it cannot resolve the charset UTF-8*EN-US and returns an empty string. The recommended_filename() method returns that empty string rather than falling back to the name parameter.\n\nOther mail readers return payload.exe. A remote sender can get an attachment past a policy that checks file extensions on the recommended filename.\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":[]}