Cars require seatbelts. Pill bottles need safety caps. Applications need web application firewalls, and for good reason. The web application threat landscape is in a constant state of flux. From DevOps to new attack vectors, these changes can leave security professionals scrambling to safeguard their most prized digital assets to secure the customer experience.
The Open Web Application Security Project (OWASP) Top 10 list is an invaluable tool for
accomplishing this. Since 2003, this top ten list seeks to provide security professionals with a
starting point for ensuring protection from the most common and virulent threats, application
misconfigurations that can lead to vulnerabilities, as well as detection tactics and remediations.
But just like the adaptive threat landscape it seeks to define, this list is updated to continue to serve
as an industry benchmark for the application security community. This piece provides an overview of
the 2017 OWASP Top 10 list, changes between the 2013 and 2017 version and technical capabilities
security professionals should consider when evaluating web application firewalls (WAFs).
2013 RANK: 1
#1 Threat: Injections
Injection flaws, such as SQL, NoSQL, OS and LDAP injection, have been a perennial favorite among hackers for
some time, which is why it’s no surprise that this threat is still at the top of the list. An injection flaw occurs when
suspicious data is inserted into an application as a command or query. This hostile data can trick the interpreter
into executing unintended commands or accessing data without proper authorization.
The most common code injection are SQL Injections, which is an attack that is accomplished by sending
malformed code to the database server. It’s a simple, quick and easy attack type that almost anyone with
Internet access can accomplish; SQL Injection scripts are available for download and are easily acquirable.
COUNTERMEASURE: POSITIVE PROTECTION
Many web application security solutions leverage a negative security model, which defines what is
disallowed while implicitly allowing everything else. Since attack signatures may generate false positives
by detecting legitimate traffic as attack traffic, such rules tend to be simplistic, trying to detect the obvious
attacks. The result is protection against the lowest common denominator.
A positive security model, which defines the set of allowed types and values, is required to provide proper
protection where signature-based protection cannot fill the gap. In the case of SQL Injections, a positive
security model screens user input for known patterns of attacks and leverages logic to tell the difference
between legitimate user input and injection flaws.
2013 RANK: 2
#2 Threat: Broken Authentication
When an application’s functions are not implemented correctly, the door is left open for criminals to break in.
Attackers can compromise passwords, keys, or session tokens or exploit other implementation flaws to assume
other users’ identities temporarily or permanently. Sessions should be unique to individual users, and without
some session management, an attacker can sneak in disguised as a user to access valuable data.
COUNTERMEASURE: CHALLENGE AND VALIDATE
Securing these application in terms of access control is no easy task. Authenticating users by having them
provide their identity and challenging them to verify their identity is a key first step. Single sign-on and
multi-factor authentication is a key first step that reduces the risk of compromised accounts.
Second is a web application firewall that proactively encrypts session parameters between network and client,
proactively inspects login attempts and thwarts HTTP sessions via code-encrypting, cryptographic capabilities.
2013 RANK: 6
#3 Threat: Sensitive Data Exposure
Many web applications and APIs contain vulnerabilities due to coding, thereby exposing sensitive data, such
as financial, healthcare, and PII. Attackers may steal or modify such weakly protected data to conduct credit
card fraud, identity theft or other crimes. Sensitive data may be compromised without extra protection, such as
encryption at rest or in transit, and requires special precautions when exchanged with the browser.
COUNTERMEASURE: ENCRYPTION, EITHER ON THE MOVE OR SITTING IN PLACE
Encryption is key, both for data at rest or in transit. Leading web application firewalls provide inspection/encryption of data, including SSL inspection and protection capabilities to eliminate security blind spots.
This includes, but is not limited to, SSL traffic decryption and encryption, masking server identities and
veiling sensitive information such as credit card numbers and social security numbers. An adaptive WAF
that leverages auto policy generation and machine-learning capabilities to automatically create and apply
security configurations and policies is also critical. Finally, any enterprise-grade firewall should support the
encryption of ingress and egress traffic across both on-premise and cloud-based infrastructures.
NEW IN 2017
#4 Threat: XML External Entities
Many older or poorly configured XML processors evaluate external entity references within XML documents.
Attackers can use external entities for attacks, including remote code execution and to disclose internal files,
SMB file shares, conduct internal port scanning and to launch DoS attacks.
COUNTERMEASURE: AN INTEGRATED APPROACH
Static application security testing (SAST) is a tried and true way to discover this issue by inspecting
dependencies and configuration. Its brethren, Dynamic Application Security Testing (DAST) are tools to
detect vulnerabilities in application in its running state.
A WAF should be able to parse and inspect protcols and structured documents, including HTTP/HTTPS
traffic, POST requests and XML JSON schemas. In addition, the aforementioned machine-learning
algorithms can learn XML and JSON structures and schemas for enforcement as part of the validation
phase and create security policies.
MERGED RISKS 4 & 7 2013
#5 Threat: Broken Access Control
Improperly configured or missing restrictions on authenticated users allow them to access unauthorized
functionality or data. Attackers can exploit these flaws to access unauthorized functionality and/or data, such as
access other users’ accounts, view sensitive files, modify other users’ data, change access rights, etc.
COUNTERMEASURE: FASTEST TIME TO PROTECTION
Penetration testing is essential for detecting non-functional access controls; other testing methods only detect
where access controls are missing. The problem is it can take several weeks to test, produce and assess
these reports, and then implement necessary security changes. This problem can be exasperated when four
out of five organizations report at least a medium degree of manual work to make security policy updates to
their WAF, according to Radware’s 2017-2018 Global Application & Network Security Report.
Any web application firewall should serve as a catalyst for stemming unauthorized access via authentication
gateway functionality, single sign-on, user tracking and access controls to the web application based on
user role and profile information.
2013 Rank: 5
#6 Threat: Security Misconfiguration
Security misconfiguration remains one of the most commonly seen web application security issues to this day.
This risk refers to improper implementation of controls intended to keep application data safe, such as insecure
default configurations, incomplete or ad hoc configurations, open cloud storage, misconfigured HTTP headers, and
perhaps most importantly, not patching or upgrading systems, frameworks, libraries, applications and components.
COUNTERMEASURE: THE ABILITY TO LEARN
As notable ransomware and malware outbreaks in recent years (i.e. WannaCry) has proven, system
upgrades are critical. An “adaptive” WAF will leverage auto policy generation and machine-learning
capabilities to automatically create and apply security filters and enforcement rules where security is
misconfigured. It evaluates the structure of a web application, sets relevant security filters and analyzes
traffic properties from a production environment to build a dynamic network profile, thereby maximizing
security while minimizing false positives.
2013 Rank: 3
#7 Threat: Cross-site Scripting(XSS)
Cross-site scripting (XSS) flaws occur whenever an application includes untrusted data in a new webpage
without proper validation or updates an existing webpage with user-supplied data using a browser API that
application to hijack user sessions, deface websites or redirect the user to malicious sites.
COUNTERMEASURE: A CHECKLIST
Against cross-site scripting attempts, make sure any web application firewall can checkoff the following:
signature- and rule-based protection with updated signatures (similar to a blacklist) and the ability to
identify scripting patterns and blocking malicious requests.
NEW IN 2017
#8 Threat: Insecure Deserialization
Insecure deserialization often leads to remote code execution to tamper or delete serialized objects or elevate
privileges. Even if deserialization flaws do not result in remote code execution, they can be used to perform
attacks, including replay or injection attacks.
COUNTERMEASURE: BEST OF BOTH WORLDS
Identify web application firewalls that provide the best of both worlds: they combine negative (defining what
is forbidden and accepting the rest) and positive security models (defining what is allowed and rejecting
the rest). This winning combination should leverage various WAF access control filters such as cookie
encryption, XML/JSON parsing, parameters enforcement and more.
2013 RANK: 9
#9 Threat: Using Components with Known Vulnerabilities
Components, such as libraries, frameworks, and other software modules, run with the same privileges as
the application. If a vulnerable component is exploited, such an attack can facilitate serious data loss or
server takeover. Developers frequently don’t know which open source or third-party components are in
their applications, making it difficult to update components when new vulnerabilities are discovered. These
components can undermine application defenses and enable various attacks and impacts.
COUNTERMEASURE: KNOW WHERE THE HOLES EXIST
Any web application firewall that provides integration with programs such as Microsoft’s Server Update
Services allows the WAF to protect against exploitations of components with known vulnerabilities by
screening client requests and server responses. In addition, security updates and threat intelligence feeds
are essential to keep security teams in the know and facilitate quicker responses. for real-time responses to
maximize protection and reduce exposure.
NEW IN 2017
#10 Threat: Insufficient Logging & Monitoring
Insufficient logging and monitoring, coupled with missing or ineffective integration with incident response
systems, allows attackers to run amok, attacking further systems, tampering, extracting or destroying data.
Many studies show that time to detect is measured in weeks or months, typically detected by external parties
rather than internal processes or monitoring.
COUNTERMEASURE: SUITE SOLUTIONS VERSUS BEST-OF-BREED
To address the issue of internal processes, think like an attacker and internally test and audit to discover
if your organization has sufficient monitoring. If your organization lacks this “white hat hacker” expertise,
be sure that any cyber security vendor you partner with provides DDoS mitigation expertise via a team of
battle-hardened security experts.
These same experts should also play a role in the second biggest concern: real-time monitoring and detection.
Timely detection of malicious malware or snooping hackers comes down to best-of-breed versus suite offerings.
Stopping cyber-attacks in near real-time is best accomplished via a single vendor attack mitigation system.
Many organizations leverage best-of-breed mitigation tools from different vendors. This hodgepodge collection
results in poor communication and detection. Suite WAF/DDoS solutions can more effectively communicate,
setting network traffic baselines and comparing data points to quickly detect when something is awry, in
addition to providing enterprise-grade monitoring and management dashboards/analytics.
The OWASP Top 10 is not intended as “one list to rule them all,” but rather serves as a great starting point for
application security programs and web application firewall evaluation. It serves as a benchmark for empowering
improved people, processes and technology.
Successful organizations must establish and use repeatable processes and security controls, testers should
establish continuous application security testing, application managers need to take charge of the application
lifecycle and the organization as a whole needs to have an application security program in place that effectively
coordinates across all facets of its infrastructure.
To that end, selecting the right WAF vendor to partner with is a critical step in executing these concepts. Be sure
any WAF solution your organization is evaluating not only meets your organization’s existing security needs, but
is flexible enough to adapt to future infrastructure environments, business needs and attack vectors.