Alerts started firing from a system server sitting in the DMZ at
a remote site of an oil producer. Analysts concluded that a
vulnerability scanner had identified a significant security hole.
Several e-mails, a few phone calls, and within a few minutes the
organization had the information it needed.
The facts: The system in question was responsible for forwarding
reports, which would be double-checked using other methods. It
wasn’t tied into any critical operations, it was relatively
isolated, it didn’t contain overly sensitive information, and
exposure wouldn’t affect nearby systems. And it was very
remote. Patching would mean putting an IT person on a plane. The
company decided that flying an IT administrator out to immediately
patch wasn’t worth the trouble or expense. The alert was
noted and scheduled to be handled the next time someone did routine
maintenance on the server.
The lesson here: For effective vulnerability management, apply risk
management principles and logic relative to the business value.
Today’s vulnerability landscape is mined with custom
application exposures, infrastructure deficiencies like improperly
secured wireless networks, and desktop- and end-user-centric attack
methods. As recent breaches have illustrated, a criminal element
has moved us from a world of chatty and poorly developed worms to
one of stealthy, professionally developed, targeted malware.
IT must work with business units to determine a company-wide
security posture that is within acceptable risk tolerance levels,
create operational processes that address the computing environment
as a whole, and select the right technology platforms to bolster
those processes.
A Working Process
Effective
vulnerability management programs require the right balance of
technology, business intelligence, and process.
Necessary technology includes vulnerability scanners, such as
McAfee’s FoundScan, Qualys’ QualysScan, or Tenable
Network Security’s Nessus; application scanners, such as
Hewlett-Packard’s WebInspect and IBM’s AppScan; and
configuration and patch management tools. However, without several
critical vulnerability management processes, these tools
won’t be as effective.
One vital process is reducing the exposure a company presents to
adversaries—sometimes called “attack surface
reduction.” The term “attack surface” can refer
to a program’s susceptibility to various avenues of attack or
to systems as a whole. Companies often use a combination of network
design exercises, access management, and configuration management
to reduce attack surfaces. For example, a system’s attack
surface can be reduced by exposing only required services to the
network, disabling or removing unnecessary software, or limiting
the number of users authorized to log on to a system.
An effective vulnerability management program also can help manage
a company’s overall security posture and risk tolerance. By
aggregating vulnerability and incident data, IT can improve
security. Trending and data correlation help show how internal
activities and external events affect a company’s risk
profile. This analysis helps gauge the success of projects, such as
patching and system maintenance, while identifying areas where more
investment is needed.
Another benefit to vulnerability management programs is they that
can help achieve compliance objectives. Technical standards,
operational frameworks, regulations such as Sarbanes-Oxley, and
industry-specific frameworks such as HIPAA and PCI have spurred
companies to implement controls and report on their success. An
effective vulnerability management program can help demonstrate
compliance with established controls, as well as alert management
to compliance problems. Tools and data correlation within a mature
vulnerability management program can extract stats about default
password length, expiration, and complexity requirements, and pull
them into compliance reports.
Nevertheless, we’ve watched organizations sink a lot of money
into security tools and elaborate scanning deployments, only to see
teams stuck reviewing similar results, report after report, month
after month, year after year. The monthly patch cycle is a
necessary but relatively well-understood evil that likely
won’t end anytime soon. However, most companies regularly
find problems in homegrown apps, missing patches that are quite a
bit older than 30 days, and devices that aren’t compliant
with approved standards. Many of the failures leading to these
findings are systemic in nature, and the ability to address root
causes is often what separates an effective vulnerability
management program from an ineffective one.
So how do we break the cycle of ineffectiveness? A few steps are
critical.
Step 1: Integrate Data
Collection
The effectiveness of a vulnerability management program is highly
dependent not just on the technologies used but on the integration
among components. Vulnerability identification systems, such as
vulnerability scanners and system policy and device configuration
audit tools, provide a basis for gathering data, but tight
integration with change management software also is needed.
Configuration management, patch management, and identity and access
management tools automate system maintenance and provide a
real-time view of system and device state. Integrating these
products with vulnerability identification tools gives a company a
holistic picture of vulnerabilities and risks in its environment.
That said, integrating maintenance and vulnerability identification
systems is easier said than done.

The key is to identify which elements are crucial to the program.
We recommend taking a top-down approach. For example, companies
should take inventory of the systems and data they have in
production. Key stakeholders should review the state of those
systems, evaluate the organization’s operational capacity to
implement changes, and ask high-level questions that support a
higher security posture. How many Windows systems do we have in a
given region? What is our exposure to Apache problems? As IT teams
compile the answers, they should gather the information needed to
act as well. If there are 100 Windows systems in Europe, is that
enough information? Do I need to know MAC addresses? Asset
owners?
Additional technology should only be considered once these
questions have been answered.
Step 2: Prioritize
Prioritization is always crucial in IT, but its importance is only
amplified in challenging times. Clearly, vulnerability management
must be deployed in a way that allows for easy prioritization. This
typically means establishing groups of assets, to improve data
collection effectiveness; and groups of owners, to facilitate
relevant and actionable reporting. Groups often are built along
regional, operational (accounting, facilities), or technological
boundaries (desktop group, Unix team). When determining security
posture, asset groups should be aligned with business functions.
Groups must be a manageable size, with clearly defined
responsibilities.
In the case of attack surface reduction, ownership groups include
IT managers, data center owners, and others responsible for
maintaining the security and integrity of systems. When addressing
company-wide security, ownership groups typically include members
of the security organization, internal auditors, and, potentially,
business units. Compliance-oriented ownership groups should be
aligned with individuals responsible for enforcing and reporting on
compliance.
Step 3: Continue to Refine
Part of continuous improvement includes understanding how
individual characteristics affect vulnerability management program
objectives. The table above outlines the way seven characteristics
relate to the objectives of vulnerability management.
When determining security posture or compliance level, quality data
is paramount. Missed vulnerabilities will create a false sense of
security, and poor data can generate “false
positives”—nonexistent vulnerabilities. Data should be
collected frequently when reducing attack surface is the top
priority, but is not critical for determining security posture. The
frequency of data collection for compliance initiatives will be
specific to individual compliance requirements.
Trending is most useful for understanding security posture, success
of vulnerability reduction efforts, and compliance-related
activities. Trending information will show how an
organization’s risk profile changes over time and how
external events, such as vulnerabilities and patch releases, impact
enterprise-wide security posture.
False positives often erroneously show vulnerabilities and
configuration errors where none exist. Trending can reduce false
positives, but they can still have a significant impact on
compliance activities, because an accurate picture of
vulnerabilities is vital for compliance reporting.