US-CERT Technical Cyber Security Alert TA12-024A warns of Anonymous DDoS attacks

Anonymous has made the news lately with their attacks on many sites, with the most prominent being government sites. US-CERT released this info yesterday:


National Cyber Alert System

Technical Cyber Security Alert TA12-024A

“Anonymous” DDoS Activity

Original release date: January 24, 2012

Last revised: —

Source: US-CERT


US-CERT has received information from multiple sources about

coordinated distributed denial-of-service (DDoS) attacks with

targets that included U.S. government agency and entertainment

industry websites. The loosely affiliated collective “Anonymous”

allegedly promoted the attacks in response to the shutdown of the

file hosting site MegaUpload and in protest of proposed U.S.

legislation concerning online trafficking in copyrighted

intellectual property and counterfeit goods (Stop Online Piracy

Act, or SOPA, and Preventing Real Online Threats to Economic

Creativity and Theft of Intellectual Property Act, or PIPA).



I. Description


US-CERT has evidence of two types of DDoS attacks: One using HTTP

GET requests and another using a simple UDP flood.


The Low Orbit Ion Cannon (LOIC) is a denial-of-service attack tool

associated with previous Anonymous activity. US-CERT has reviewed

at least two implementations of LOIC. One variant is written in

JavaScript and is designed to be used from a web browser. An

attacker can access this variant of LOIC on a website and select

targets, specify an optional message, throttle attack traffic, and

monitor attack progress. A binary variant of LOIC includes the

ability to join a botnet to allow nodes to be controlled via IRC or

RSS command channels (the “HiveMind” feature).


The following is a sample of LOIC traffic recorded in a web server



“GET /?id=1327014400570&msg=We%20Are%20Legion! HTTP/1.1” 200

99406 “hxxp://” “Mozilla/5.0

(Windows NT 6.1; WOW64; rv:9.0.1) Gecko/20100101 Firefox/9.0.1”


The following sites have been identified in HTTP referrer headers

of suspected LOIC traffic. This list may not be complete. Please do

not visit any of the links as they may still host functioning LOIC

or other malicious code.






















The following are the A records for the referrer sites as of

January, 20, 2012:


3g[.]bamatea[.]com                A    218[.]5[.]113[.]218

cybercrime[.]hostzi[.]com         A    31[.]170[.]161[.]36

event[.]seeho[.]co[.]kr           A    210[.]207[.]87[.]195

chatimpacto[.]org                 A    66[.]96[.]160[.]151

anonymouse[.]org                  A    193[.]200[.]150[.]125

pastehtml[.]com                   A    88[.]90[.]29[.]58

lcnongjipeijian[.]com             A    49[.]247[.]252[.]105

www[.]rotterproxy[.]info          A    208[.]94[.]245[.]131

www[.]tandycollection[.]co[.]kr   A    121[.]254[.]168[.]87

www[.]zgon[.]cn                   A    59[.]54[.]54[.]204

www[.]turbytoy[.]com[.]ar         A    190[.]228[.]29[.]84


The HTTP requests contained an “id” value based on UNIX time and

user-defined “msg” value, for example:


GET /?id=1327014189930&msg=%C2%A1%C2%A1NO%20NOS%20GUSTA%20LA%20


Other “msg” examples:







msg=Stop%20S.O.P.A%20:)%20%E2%99%AB%E2%99%AB HTTP/1.1″ 200 99406










The “msg” field can be arbitrarily set by the attacker.


As of January 20, 20012, US-CERT has observed another attack that

consists of UDP packets on ports 25 and 80. The packets contained a

message followed by variable amounts of padding, for example:


66:6c:6f:6f:64:00:00:00:00:00:00:00:00:00 | flood………


Target selection, timing, and other attack activity is often

coordinated through social media sites or online forums.


US-CERT is continuing research efforts and will provide additional

data as it becomes available.



II. Solution


There are a number of mitigation strategies available for dealing

with DDoS attacks, depending on the type of attack as well as the

target network infrastructure. In general, the best practice

defense for mitigating DDoS attacks involves advanced preparation.


* Develop a checklist or Standard Operating Procedure (SOP) to

follow in the event of a DDoS attack. One critical point in a

checklist or SOP is to have contact information for your ISP and

hosting providers. Identify who should be contacted during a

DDoS, what processes should be followed, what information is

needed, and what actions will be taken during the attack with

each entity.

* The ISP or hosting provider may provide DDoS mitigation services.

Ensure your staff is aware of the provisions of your service

level agreement (SLA).

* Maintain contact information for firewall teams, IDS teams,

network teams and ensure that it is current and readily available.

* Identify critical services that must be maintained during an

attack as well as their priority. Services should be prioritized

beforehand to identify what resources can be turned off or

blocked as needed to limit the effects of the attack. Also,

ensure that critical systems have sufficient capacity to

withstand a DDoS attack.

* Have current network diagrams, IT infrastructure details, and

asset inventories. This will assist in determining actions and

priorities as the attack progresses.

* Understand your current environment and have a baseline of daily

network traffic volume, type, and performance. This will allow

staff to better identify the type of attack, the point of attack,

and the attack vector used. Also, identify any existing

bottlenecks and remediation actions if required.

* Harden the configuration settings of your network, operating

systems, and applications by disabling services and applications

not required for a system to perform its intended function.

* Implement a bogon block list at the network boundary.

* Employ service screening on edge routers wherever possible in

order to decrease the load on stateful security devices such as


* Separate or compartmentalize critical services:


* Separate public and private services

* Separate intranet, extranet, and internet services

* Create single purpose servers for each service such as HTTP,

FTP, and DNS

* Review the US-CERT Cyber Security Tip Understanding

Denial-of-Service Attacks.



III. References


* Cyber Security Tip ST04-015 –



* Anonymous&apos;s response to the seizure of MegaUpload according to




* The Internet Strikes Back #OpMegaupload –



* Twitter Post from the author of the JavaScript based LOIC code –



* Anonymous Operations tweets on Twitter –



* @Megaupload Tweets on Twitter –



* LOIC DDoS Analysis and Detection –



* Impact of Operation Payback according to CNN –



* OperationPayback messages on YouTube –



* The Bogon Reference – Team Cymru –





The most recent version of this document can be found at:





Feedback can be directed to US-CERT Technical Staff. Please send

email to <> with “TA12-024A Feedback INFO#919868” in

the subject.



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Produced 2012 by US-CERT, a government organization.


Terms of use:





Revision History


January 24, 2012: Initial release


If you require assistance with DDoS or any other security need for your Greenville or Upstate SC business, please call upon us at 864.990.4748 or email

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