U.S. Department of Homeland Security US-CERT

National Cyber Awareness System:


TA16-288A: Heightened DDoS Threat Posed by Mirai and Other Botnets [ 
https://www.us-cert.gov/ncas/alerts/TA16-288A ] 10/14/2016 07:59 PM EDT
Original release date: October 14, 2016

Systems Affected

Internet of Things (IoT)—an emerging network of devices (e.g., printers, 
routers, video cameras, smart TVs) that connect to one another via the 
Internet, often automatically sending and receiving data

Overview

Recently, IoT devices have been used to create large-scale botnets—networks of 
devices infected with self-propagating malware—that can execute crippling 
distributed denial-of-service (DDoS) attacks. IoT devices are particularly 
susceptible to malware, so protecting these devices and connected hardware is 
critical to protect systems and networks.

Description

On September 20, 2016, Brian Krebs’ security blog (krebsonsecurity.com) was 
targeted by a massive DDoS attack, one of the largest on record, exceeding 620 
gigabits per second (Gbps).[1 [ 
https://krebsonsecurity.com/2016/09/krebsonsecurity-hit-with-record-ddos/ ]]
An 
IoT botnet powered by Mirai malware created the DDoS attack. The Mirai malware 
continuously scans the Internet for vulnerable IoT devices, which are then 
infected and used in botnet attacks. The Mirai bot uses a short list of 62 
common default usernames and passwords to scan for vulnerable devices. Because 
many IoT devices are unsecured or weakly secured, this short dictionary allows 
the bot to access hundreds of thousands of devices.[2 [ 
https://nakedsecurity.sophos.com/2016/10/05/mirai-internet-of-th
ngs-malware-fr 
om-krebs-ddos-attack-goes-open-source/ ]] The purported Mirai author claimed 
that over 380,000 IoT devices were enslaved by the Mirai malware in the attack 
on Krebs’ website.[3 [ 
https://www.pcworld.com/article/3126362/security/iot-malware-beh
nd-record-ddos 
-attack-is-now-available-to-all-hackers.html ]]

In late September, a separate Mirai attack on French webhost OVH broke the 
record for largest recorded DDoS attack. That DDoS was at least 1.1 terabits 
per second (Tbps), and may have been as large as 1.5 Tbps.[4 [ 
http://arstechnica.com/security/2016/09/botnet-of-145k-cameras-r
portedly-deliv 
er-internets-biggest-ddos-ever/ ]]

The IoT devices affected in the latest Mirai incidents were primarily home 
routers, network-enabled cameras, and digital video recorders.[5 [ 
http://www.darkreading.com/denial-of-service-attacks/iot-ddos-at
ack-code-relea 
sed-/d/d-id/1327086 ]] Mirai malware source code was published online at the 
end of September, opening the door to more widespread use of the code to
create 
other DDoS attacks.

In early October, Krebs on Security reported on a separate malware family 
responsible for other IoT botnet attacks.[6 [ 
https://krebsonsecurity.com/2016/10/source-code-for-iot-botnet-mirai-released/ 
]] This other malware, whose source code is not yet public, is named Bashlite. 
This malware also infects systems through default usernames and passwords. 
Level 3 Communications, a security firm, indicated that the Bashlite botnet
may 
have about one million enslaved IoT devices.[7 [ 
http://blog.level3.com/security/attack-of-things/ ]]

Impact

With the release of the Mirai source code on the Internet, there are increased 
risks of more botnets being generated. Both Mirai and Bashlite can exploit the 
numerous IoT devices that still use default passwords and are easily 
compromised. Such botnet attacks could severely disrupt an organization’s 
communications or cause significant financial harm.

Software that is not designed to be secure contains vulnerabilities that can
be 
exploited. Software-connected devices collect data and credentials that could 
then be sent to an adversary’s collection point in a back-end application.

Solution

Cybersecurity professionals should harden networks against the possibility of
a 
DDoS attack. For more information on DDoS attacks, please refer to US-CERT 
Security Publication DDoS Quick Guide [ 
https://www.us-cert.gov/sites/default/files/publications/DDoS%20
uick%20Guide.p 
df ] and the US-CERT Alert on UDP-Based Amplification Attacks [ 
https://www.us-cert.gov/ncas/alerts/TA14-017A ].

*"Mitigation"*

In order to remove the Mirai malware from an infected IoT device, users and 
administrators should take the following actions:


  * Disconnect device from the network.
  * While disconnected from the network and Internet, perform a reboot.
Because 
Mirai malware exists in dynamic memory, rebooting the device clears the 
malware.
  * Ensure that the password for accessing the device has been changed from
the 
default password to a strong password. See US-CERT Tip Choosing and Protecting 
Passwords [ https://www.us-cert.gov/ncas/tips/ST04-002 ] for more information.
  * You should reconnect to the network only after rebooting and changing the 
password. If you reconnect before changing the password, the device could be 
quickly reinfected with the Mirai malware.

*"Preventive Steps"*

In order to prevent a malware infection on an IoT device, users and 
administrators should take following precautions:


  * Ensure all default passwords are changed to strong passwords. Default 
usernames and passwords for most devices can easily be found on the Internet, 
making devices with default passwords extremely vulnerable.
  * Update IoT devices with security patches as soon as patches become 
available.
  * Disable Universal Plug and Play (UPnP) on routers unless absolutely 
necessary.[8 [ https://www.ic3.gov/media/2015/150910.aspx ]]
  * Purchase IoT devices from companies with a reputation for providing secure 
devices.
  * Consumers should be aware of the capabilities of the devices and
appliances 
installed in their homes and businesses. If a device comes with a default 
password or an open Wi-Fi connection, consumers should change the password and 
only allow it to operate on a home network with a secured Wi-Fi router.
  * Understand the capabilities of any medical devices intended for at-home 
use. If the device transmits data or can be operated remotely, it has the 
potential to be infected.
  * Monitor Internet Protocol (IP) port 2323/TCP and port 23/TCP for attempts 
to gain unauthorized control over IoT devices using the network terminal 
(Telnet) protocol.[9 [ 
https://isc.sans.edu/forums/diary/What+is+happening+on+2323TCP/21563/ ]]
  * Look for suspicious traffic on port 48101. Infected devices often attempt 
to spread malware by using port 48101 to send results to the threat actor.

References

  * [1] KrebsOnSecurity: KrebsOnSecurity Hit With Record DDoS [ 
https://krebsonsecurity.com/2016/09/krebsonsecurity-hit-with-record-ddos/ ]
  * [2] Sophos: Mirai “internet of things” malware from Krebs DDoS attack goes 
open source [ 
https://nakedsecurity.sophos.com/2016/10/05/mirai-internet-of-th
ngs-malware-fr 
om-krebs-ddos-attack-goes-open-source/ ]
  * [3] PCWorld: Smart device malware behind record DDoS attack is now 
available to all hackers [ 
https://www.pcworld.com/article/3126362/security/iot-malware-beh
nd-record-ddos 
-attack-is-now-available-to-all-hackers.html ]
  * [4] ArsTechnica: Record-breaking DDoS reportedly delivered by >145k hacked 
cameras [ 
http://arstechnica.com/security/2016/09/botnet-of-145k-cameras-r
portedly-deliv 
er-internets-biggest-ddos-ever/ ]
  * [5] InformationWeek DarkReading: IoT DDoS Attack Code Released [ 
http://www.darkreading.com/denial-of-service-attacks/iot-ddos-at
ack-code-relea 
sed-/d/d-id/1327086 ]
  * [6] KrebsOnSecurity: Source Code for IoT Botnet "Mirai" Released [ 
https://krebsonsecurity.com/2016/10/source-code-for-iot-botnet-mirai-released/ 
]
  * [7] Level 3 Threat Research Labs: Attack of Things! [ 
http://blog.level3.com/security/attack-of-things/ ]
  * [8] Federal Bureau of Investigation Public Service Announcement: Internet 
of Things Poses Opportunities for Cyber Crime [ 
https://www.ic3.gov/media/2015/150910.aspx ]
  * [9] SANS ISC InfoSec Forums: What is happening on 2323/TCP? [ 
https://isc.sans.edu/forums/diary/What+is+happening+on+2323TCP/21563/ ]

Revision History

  * October 14, 2016: Initial release
________________________________________________________________________

This product is provided subject to this Notification [ 
http://www.us-cert.gov/privacy/notification ] and this Privacy & Use [ 
http://www.us-cert.gov/privacy/ ] policy.

________________________________________________________________________

A copy of this publication is available at www.us-cert.gov [ 
https://www.us-cert.gov ]. If you need help or have questions, please send an 
email to info@us-cert.gov. Do not reply to this message since this email was 
sent from a notification-only address that is not monitored. To ensure you 
receive future US-CERT products, please add US-CERT@ncas.us-cert.gov to your 
address book.

OTHER RESOURCES: Contact Us [ http://www.us-cert.gov/contact-us/ ] | Security 
Publications [ http://www.us-cert.gov/security-publications ] | Alerts and
Tips 
[ http://www.us-cert.gov/ncas ] | Related Resources [ 
http://www.us-cert.gov/related-resources ]

STAY CONNECTED: Sign up for email updates [ 
http://public.govdelivery.com/accounts/USDHSUSCERT/subscriber/new ]

SUBSCRIBER SERVICES:
Manage Preferences [ 
http://public.govdelivery.com/accounts/USDHSUSCERT/subscribers/n
w?preferences= 
true ]  |  Unsubscribe [ 
https://public.govdelivery.com/accounts/USDHSUSCERT/subscriber/o
e_click_unsubs 
cribe?verification=5.43e66354f7e069837b41e0fec3b03174&destinatio
=Fido4cmech%40 
lusfiber.net ]  |  Help [ https://subscriberhelp.govdelivery.com/ ]

________________________________________________________________________

This email was sent to Fido4cmech@lusfiber.net using GovDelivery, on behalf
of: 
United States Computer Emergency Readiness Team (US-CERT) · 245 Murray Lane SW 
Bldg 410 · Washington, DC 20598 · (888) 282-0870  Powered by GovDelivery [ 
http://www.govdelivery.com/portals/powered-by ]




-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2016.0.7797 / Virus Database: 4664/13210 - Release Date: 10/14/16

=== Cut ===


-+-
Keep the faith   :^)

   Ben  aka cMech  Web: http|ftp|binkp|telnet://cmech.dynip.com
                 Email: fido4cmech(at)lusfiber.net
              Home page: http://cmech.dynip.com/homepage/
           WildCat! Board 24/7  +1-337-984-4794  any BAUD 8,N,1

... My computer's sick. I think my modem is a carrier.
--- GoldED+/W32-MSVC v1.1.5 via Mystic BBS
 * Origin: FIDONet - The Positronium Repository (1:393/68)