CSAM: ANY queries used in reflective DoS attack

Published: 2013-10-08
Last Updated: 2013-10-08 21:19:20 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)

Our reader Phillip sent in the following log excerpt:

15:53:34.329883 IP > 59.167.x.35.53: 9158+ [1au] ANY? hizbullah.me. (41)
15:53:34.331562 IP > 59.167.x.36.53: 9158+ [1au] ANY? hizbullah.me. (41)
15:53:34.331785 IP > 59.167.x.32.53: 9158+ [1au] ANY? hizbullah.me. (41)
15:53:34.332050 IP > 59.167.x.39.53: 9158+ [1au] ANY? hizbullah.me. (41)
15:58:56.288188 IP > 59.167.x.32.53: 17253+ [1au] A? 4fwhk.com. (50)
15:59:23.345810 IP > 59.167.x.34.53: 28322+ [1au] A? 4fwhk.com. (50)

There are a couple of indicators that these logs are "odd":

- ANY queries are unusual in normal DNS traffic. While they are valid, they are not often used in "normal" DNS traffic. But for DoS attacks, they provide large responses.
- the source port and the query ID doesn't change
- the speed of these queries is very fast.

The main "feature" of hizbullah.me becomes obvious if you look at the size of the response:

$ dig ANY hizbullah.me
;; Truncated, retrying in TCP mode.
; <<>> DiG 9.8.5-P1 <<>> ANY hizbullah.me
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39771
;; flags: qr rd ra; QUERY: 1, ANSWER: 244, AUTHORITY: 1, ADDITIONAL: 1
;hizbullah.me. IN ANY
hizbullah.me. 3589 IN SOA ns1.hizbullah.me. admin.hizbullah.me. 2012292301 28800 86400 3600000 86400
hizbullah.me. 1789 IN A
hizbullah.me. 1789 IN A
hizbullah.me. 1789 IN A
hizbullah.me. 1789 IN A
hizbullah.me. 1789 IN NS ns1.hizbullah.me.
hizbullah.me. 1789 IN NS ns1.hizbullah.me.
ns1.hizbullah.me. 3588 IN A
;; Query time: 7 msec
;; WHEN: Tue Oct 08 17:09:00 EDT 2013
;; MSG SIZE  rcvd: 3992

I removed most of the "A" record responses. There are a total of 243 if I counted right. The response is 3992 bytes, almost 100 times the size of the query (41 bytes). You also see at the top how dig indicates that it had to fall back to TCP because the response was too large. Many modern resolvers don't require this, and use EDNS0 to allow larger responses, typically up to 4kBytes in size.

The hizbullah.me domain appears to be set up just to act as a source of large DNS responses to be used in DoS attacks.

The second record no longer resolves. I can only assume that it was used similarly. The "ANY" query is not needed for a domain like hizbullah.me with many A records. Just an A query will result in a huge answer.



Johannes B. Ullrich, Ph.D.
SANS Technology Institute

Keywords: any csam dns dos
0 comment(s)

Microsoft October 2013 Patch Tuesday

Published: 2013-10-08
Last Updated: 2013-10-08 17:30:03 UTC
by Johannes Ullrich (Version: 1)
3 comment(s)

Overview of the October 2013 Microsoft patches and their status.

# Affected Contra Indications - KB Known Exploits Microsoft rating(**) ISC rating(*)
clients servers
MS13-080 Cumulative Security Update for Internet Explorer
(ReplacesMS13-069 )
Internet Explorer
KB 2879017 Yes. Severity:Critical
Exploitability: 1
PATCH NOW! Critical
MS13-081 Vulnerabilities in Windows Kernel-Mode Drivers Could Allow Remote Code Execution
(ReplacesMS13-076 MS13-078 MS13-054 MS13-046 )
Kernel Mode Drivers (OpenType Font Parsing and others)
KB 2870008 No. Severity:Critical
Exploitability: 1,2
Critical Important
MS13-082 Vulnerabilities in .NET Framework Could Allow Remote Code Execution
(ReplacesMS13-040 MS11-100 MS13-052 )
Microsoft .NET Framework (OpenType font)
KB 2878890 CVE-2013-3861 was publically disclosed. Severity:Critical
Exploitability: 1,2,3
Critical Importantl
MS13-083 Vulnerability in Windows Common Control Library Could Allow Remote Code Execution
(ReplacesMS10-081 )
Windows Common Control Library (64 Bit versions only) DSA_InsertItem function used in webapps
KB 2864058 No. Severity:Critical
Exploitability: 1
N/A Critical
MS13-084 Vulnerabilities in Microsoft SharePoint Server Could Allow Remote Code Execution
(ReplacesMS13-067 )
KB 2885089 No. Severity:Important
Exploitability: 3,2
N/A Critical
MS13-085 Vulnerabilities in Microsoft Excel Could Allow Remote Code Execution
(ReplacesMS13-072 MS13-072 )
KB 2885080 No. Severity:Important
Exploitability: 1,2,3
Critical Less Important
MS13-086 Vulnerabilities in Microsoft Word Could Allow Remote Code Execution
(ReplacesMS13-072 )
KB 2885084 No. Severity:Important
Exploitability: 1,3
Critical Less Important
MS13-087 Vulnerability in Silverlight Could Allow Information Disclosure
(ReplacesMS13-052 )
KB 2890788 No. Severity:Important
Exploitability: 3
Important Less Important
We will update issues on this page for about a week or so as they evolve.
We appreciate updates
US based customers can call Microsoft for free patch related support on 1-866-PCSAFETY
(*): ISC rating
  • We use 4 levels:
    • PATCH NOW: Typically used where we see immediate danger of exploitation. Typical environments will want to deploy these patches ASAP. Workarounds are typically not accepted by users or are not possible. This rating is often used when typical deployments make it vulnerable and exploits are being used or easy to obtain or make.
    • Critical: Anything that needs little to become "interesting" for the dark side. Best approach is to test and deploy ASAP. Workarounds can give more time to test.
    • Important: Things where more testing and other measures can help.
    • Less Urgent: Typically we expect the impact if left unpatched to be not that big a deal in the short term. Do not forget them however.
  • The difference between the client and server rating is based on how you use the affected machine. We take into account the typical client and server deployment in the usage of the machine and the common measures people typically have in place already. Measures we presume are simple best practices for servers such as not using outlook, MSIE, word etc. to do traditional office or leisure work.
  • The rating is not a risk analysis as such. It is a rating of importance of the vulnerability and the perceived or even predicted threat for affected systems. The rating does not account for the number of affected systems there are. It is for an affected system in a typical worst-case role.
  • Only the organization itself is in a position to do a full risk analysis involving the presence (or lack of) affected systems, the actually implemented measures, the impact on their operation and the value of the assets involved.
  • All patches released by a vendor are important enough to have a close look if you use the affected systems. There is little incentive for vendors to publicize patches that do not have some form of risk to them.

(**): The exploitability rating we show is the worst of them all due to the too large number of ratings Microsoft assigns to some of the patches.

Johannes B. Ullrich, Ph.D.
SANS Technology Institute

Keywords: mspatchday
3 comment(s)

Anti-Virus Company Avira Homepage Defaced

Published: 2013-10-08
Last Updated: 2013-10-08 15:28:15 UTC
by Johannes Ullrich (Version: 1)
2 comment(s)


From Avira (http://techblog.avira.com/2013/10/08/major-dns-hijacking-affecting-major-websites-including-avira-com/en/)

"It appears that our account used to manage the DNS records registered at Network Solutions has received a fake password-reset request which was honored by the provider. Using the new credentials the cybercriminals have been able to change the entries to point to their DNS servers."


The home page of anti virus company Avira has been defaced, likely by altering the DNS zone for Avira.com. Currently, avira.com uses the following NS records:

$ dig +short avira.com NS
$ dig +short A avira.com

Once an attacker has control of the NS records, they may also change MX records and redirect e-mail, or in the case of an Antivirus company like Avira change the addresses used to download signature updates.

According to domaintools.com, the last address for avira.com was and that address still appears to host Avira's site.

A cached whois record from a couple days ago lists these DNS servers for avira.com:
The domain is hosted with Network Solutions. At this point, this looks like an isolated incident and not a more wide spread issue with Network Solutions.
I hope this will not be considered an "advanced sophisticated highly skilled attack", as the attackers have issues spelling "Palestine" consistently. The content of the defaced site is political and no malware has been spotted on the site so far.
Partial screenshot of the site:


Our reader Stuart sent us a screenshot with a similar defacement of Antivirus vendor AVG (avg.com), but the site appears to be back to normal now. I can't tell if that defacement was DNS related or not. Instant messaging software maker Whatsapp was appearently a third victim of this attack. 

Johannes B. Ullrich, Ph.D.
SANS Technology Institute

Keywords: avira defaced
2 comment(s)
ISC StormCast for Tuesday, October 8th 2013 http://isc.sans.edu/podcastdetail.html?id=3587


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