postal-mime: Quadratic CPU consumption when decoding a header of many joinable RFC 2047 base64 encoded words

影響: npm:postal-mime >= 3.0.0, < 4.0.8 → 4.0.8

Decoding a header that holds a long run of joinable RFC 2047 base64 encoded words, such as =?utf-8?B?QUJD?= repeated tens of thousands of times in a Subject, From, To, a filename or a description, took time quadratic in the number of words. The join check ran a regex over the text joined so far for every word, which flattens the accumulated string each time. A single well formed message of about 1.6 MB blocked the event loop for one to twenty seconds depending on the host, and inline message/rf…

GitHub Advisory Databaseで読む

2026/10/24 06:54、GitHub Advisory Databaseが「postal-mime: Quadratic CPU consumption when decoding a header of many joinable RFC 2047 base64 encoded words」を公開しました (種別: 脆弱性アドバイザリ)。重大度は「重要」(high) です。関連する技術: JavaScript / Node.js。