{"id":"CVE-2026-116269","state":"PUBLISHED","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","description":"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 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.","publishedAt":"2026-10-28T17:33:22.332Z","updatedAt":"2026-10-28T17:33:22.332Z","severity":null,"assigner":"CPANSec","products":["MIME-tools"],"affected":[{"packageName":"MIME-tools","packageURL":"pkg:cpan/MIME-tools","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.521","versionType":"custom"}],"collectionURL":"https://cpan.org/modules","modules":["MIME::Field::ParamVal"],"programFiles":["lib/MIME/Field/ParamVal.pm","lib/MIME/WordDecoder.pm","lib/MIME/Head.pm"],"programRoutines":[{"name":"MIME::Field::ParamVal::parse_params"},{"name":"MIME::WordDecoder::decode"},{"name":"MIME::Head::recommended_filename"}],"repo":"https://salsa.debian.org/dskoll/mime-tools"}],"references":["https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes"],"weaknesses":["CWE-436"],"ingestedAt":"2026-10-29T20:10:43.281Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/116xxx/CVE-2026-116269.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-116269","state":"PUBLISHED","datePublished":"2026-10-28T17:33:22.332Z","dateUpdated":"2026-10-28T17:33:22.332Z","assignerShortName":"CPANSec","assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","dateReserved":"2026-10-25T18:05:02.236Z"},"containers":{"cna":{"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","descriptions":[{"lang":"en","value":"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 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."}],"affected":[{"packageName":"MIME-tools","packageURL":"pkg:cpan/MIME-tools","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"5.521","versionType":"custom"}],"collectionURL":"https://cpan.org/modules","modules":["MIME::Field::ParamVal"],"programFiles":["lib/MIME/Field/ParamVal.pm","lib/MIME/WordDecoder.pm","lib/MIME/Head.pm"],"programRoutines":[{"name":"MIME::Field::ParamVal::parse_params"},{"name":"MIME::WordDecoder::decode"},{"name":"MIME::Head::recommended_filename"}],"repo":"https://salsa.debian.org/dskoll/mime-tools"}],"references":[{"url":"https://metacpan.org/release/DSKOLL/MIME-tools-5.521/changes","tags":["release-notes"]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-436","description":"CWE-436 Interpretation Conflict","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"CPANSec","orgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","dateUpdated":"2026-10-28T17:33:22.332Z"},"solutions":[{"lang":"en","value":"Upgrade to MIME-tools 5.521 or later."}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"cpansec-cna-tool 0.1"}}}}}