id summary reporter owner description type status priority milestone component version severity resolution keywords cc 5204 "wp_mail Does Not Detect Custom Boundaries in ""Multipart/Mixed"" Email Headers" Ghidra99 westi "There is a problem with the new wp_mail function. If an email is sent to wp_mail() with a custom header of ""Content-Type: multipart/mixed; boundary=""frontier"""", wp_mail() is a) not recognizing that a custom boundary has been set and b) using that custom boundary (in this case, ""frontier"") as the email character set (charset). This is producing malformed subject lines and messages in emails with non-western characters. For example, PluginX sends an email to wp_mail(). The email's headers are formed correctly: {{{ To: xxx@xxx.org Subject: =?UTF-8?B?0KHRgNC/0YHQutC4INCa0YPQu9GC?= Date: Mon, 15 Oct 2007 10:04:34 -0500 From: ""xxx@xxx.org"" MIME-Version: 1.0 Content-Type: multipart/mixed; boundary=""frontier"" --frontier Content-Type: text/plain; charset = ""UTF-8"" Content-Transfer-Encoding: 8bit Attached to this email is xxx.sql.gz Size:82 kilobytes --frontier Content-Type: application/octet-stream; name=""xxx.sql.gz"" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename=""xxx.sql.gz"" H4sIAAAAAAAAA5yMQQrCMBRE9znFQNdKWhQhWwu6sKgouLQ/yYeCNSn5UentzcITOLt585gKt5j8 --frontier }}} wp_mail() explodes and parses the email headers, incorrectly ascribing ""frontier"" as the Charset while assigning its own boundary: {{{ To: xxx@xxx.org Subject: =?frontier?B?0KHR?= =?frontier?B?gNC/?= =?frontier?B?0YHQ?= =?frontier?B?utC4?= =?frontier?B?INCa?= =?frontier?B?0YPQ?= =?frontier?B?u9GC?= Date: Mon, 15 Oct 2007 10:04:34 -0500 From: ""xxx@xxx.org"" MIME-Version: 1.0 Content-Type: multipart/mixed; boundary=""b1_49700ab183d95dd1680e0898d750b958"" --b1_49700ab183d95dd1680e0898d750b958 Content-Type: text/plain; charset = ""frontier"" Content-Transfer-Encoding: 8bit Attached to this email is xxx.sql.gz Size:82 kilobytes --b1_49700ab183d95dd1680e0898d750b958 Content-Type: application/octet-stream; name=""xxx.sql.gz"" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename=""xxx.sql.gz"" H4sIAAAAAAAAA5yMQQrCMBRE9znFQNdKWhQhWwu6sKgouLQ/yYeCNSn5UentzcITOLt585gKt5j8 --b1_49700ab183d95dd1680e0898d750b958 }}} PluginX's once correctly-formed email is now severely broken, using PluginX's custom boundary as a charset." defect (bug) closed normal 2.8 Mail 2.3 normal fixed has-patch wp_mail headers attachments