Treasury
Inspector General for Tax Administration
Office of Audit
WHILE CONTROLS HAVE BEEN IMPLEMENTED
TO ADDRESS MALWARE, CONTINUED ATTENTION IS NEEDED TO ADDRESS THIS GROWING
THREAT
Issued on March 10, 2009
Highlights
Highlights of
Report Number: 2009-20-045 to the
Internal Revenue Service Chief Technology Officer.
IMPACT ON TAXPAYERS
Malware refers
to a computer program that is inserted into a computer system with the intent
of compromising the confidentiality, integrity, or availability of an
organization’s data, applications, or operating systems. Without ongoing attention to the preventive
and response controls to address malware, Internal Revenue Service (IRS) computers
and the sensitive taxpayer data stored on them are at risk of compromise that
could ultimately result in theft of taxpayer identities and fraud.
WHY TIGTA DID THE AUDIT
This audit was initiated as part of
our statutory requirements to annually review the adequacy and security of IRS
information technology. The overall
objective of this review was to determine
whether adequate security controls are present to prevent and respond to
malware attacks.
WHAT
TIGTA FOUND
The IRS’ preventive
and response controls to address malware are generally effective; however,
continued attention should be given to limiting some practices that increase
the risk of malware incidents and increasing employee awareness of their
responsibilities for preventing malware incidents. TIGTA found that virus scans for servers are
not automated and must be manually initiated by the system administrators. TIGTA’s analysis of antivirus scans
determined that 89 percent of the servers were usually scanned weekly. The remaining servers were scanned less
frequently or not at all.
To
limit the risk of malware infection, system administrators are prohibited from
using their administrator accounts to access the Internet unless authorized by
the Chief Information Officer. In a 1-week
period in February 2008, TIGTA identified 63 administrator accounts that
successfully accessed Internet web sites a total of 820 times without
authorization. The IRS did not conduct
sufficient monitoring to ensure that administrator accounts are sufficiently
controlled to prevent compromise by malware-infected sites.
Also, employees
are not routinely contacted when their system activity results in a successful
malware incident or when their actions violate IRS policy. TIGTA believes that notifying users of their
specific activities that resulted in malware infections would serve to better
educate users about the malware threat, and that IRS management has a
responsibility to notify employees and their managers when their actions
violate IRS policies.
In addition, the
IRS mandatory annual security awareness training does not include the use of
personal portable devices and removable media as common ways in which users
can infect systems with malicious code. Of the 661 malware incidents reported in
2007, 69 (10 percent) were caused by users inserting removable media or
connecting external or portable hard drives to their systems.
WHAT TIGTA RECOMMENDED
TIGTA
recommended
that the Chief Information Officer 1) schedule automatic scans of antivirus software on servers, 2)
regularly remind administrators not to use their administrator accounts to
access the Internet and monitor Internet activity to determine whether
administrators are complying with this control, 3) notify
employees and their managers when their activity results in a successful malicious code
incident, particularly when the activity is a violation of IRS policy, and 4)
update the IRS security awareness training to include the risk of
introducing malware when using portable and removable media.
In
their response to the report, IRS officials agreed with the recommendations and
plan to take appropriate corrective actions.
The IRS plans to schedule
automated antivirus scans on servers, regularly monitor servers to ensure
antivirus scans are executed weekly, ensure administrators are regularly
reminded of Internet access restrictions, and continually monitor for Internet
access by administrator accounts and report violations for followup actions. In addition, the IRS plans to ensure
employees and their managers are notified regarding applicable cyber incidents,
and convert to the Department of the Treasury mandated information systems
security awareness training course that addresses the use of portable and
removable media as common ways that users can introduce malicious code to the
network and potential effects.
READ THE
FULL REPORT
To view the report,
including the scope, methodology, and full IRS response, go to:
http://www.treas.gov/tigta/auditreports/2009reports/200920045fr.html.
Email Address: inquiries@tigta.treas.gov
Phone Number: 202-622-6500
Web Site:
http://www.tigta.gov