Application Security Testing Tools
In cybersecurity, Application Security Testing (AST) tools are software solutions designed to identify, analyze, and help remediate security vulnerabilities and weaknesses within software applications. These tools protect applications from malicious attacks that could compromise their availability, confidentiality, and integrity. They help organizations "shift left" in the Software Development Life Cycle (SDLC), enabling detection and remediation of security issues earlier in the development process, which is generally more cost-effective and efficient.
Here's a detailed breakdown of the main types of AST tools and how they work:
1. Static Application Security Testing (SAST) Tools
How they work: SAST tools analyze an application's source code, bytecode, or binary code without executing it. They take a "white-box" approach, meaning they fully know the application's internal structure. They scan for known coding errors, insecure coding practices, and architectural flaws that could lead to vulnerabilities. SAST tools compare the code against predefined rules and patterns that identify common security weaknesses (e.g., SQL injection, cross-site scripting (XSS), buffer overflows, insecure API usage, hardcoded credentials).
When used: Typically integrated early in the SDLC, often during development (in IDEs) or in the continuous integration/continuous delivery (CI/CD) pipeline. This allows developers to get real-time feedback on vulnerabilities as they write code.
Pros:
Can identify vulnerabilities early in the development cycle, making them cheaper and easier to fix.
Provides detailed information about the exact location of the vulnerability in the code.
Can scan the entire codebase, including libraries and frameworks.
Cons:
Can produce a high number of false positives (reporting vulnerabilities that aren't exploitable).
May not detect runtime configuration issues or vulnerabilities that only manifest during execution.
Language-dependent, requiring specific tools for different programming languages.
Examples: Checkmarx, SonarQube, Semgrep, CodeQL.
2. Dynamic Application Security Testing (DAST) Tools
How they work: DAST tools test a running application from the "outside in," simulating real-world attacks. They adopt a "black-box" approach, meaning they have no prior knowledge of the application's internal code or structure. DAST tools interact with the application through its exposed interfaces (like a web browser or API client) by sending various inputs and observing its behavior and responses to identify vulnerabilities such as injection flaws, authentication issues, session management problems, and misconfigurations. They often use techniques like fuzzing (sending unexpected or malformed inputs) to uncover vulnerabilities.
When they are used: Applied to running applications, typically in testing, staging, or production environments.
Pros:
Can find vulnerabilities that only appear at runtime, such as configuration errors or server-side issues.
Language-agnostic, as they interact with the application via HTTP/S.
Can detect authentication and authorization issues, which SAST often misses.
Lower false favorable rates compared to SAST for the vulnerabilities they find.
Cons:
Can only test what is accessible externally, meaning some internal code vulnerabilities might be missed.
Typically run later in the SDLC, making discovered vulnerabilities more expensive to fix.
Requires a running instance of the application.
Examples: OWASP ZAP (Zed Attack Proxy), Burp Suite, Acunetix, Netsparker.
3. Interactive Application Security Testing (IAST) Tools
How they work: IAST tools combine elements of both SAST and DAST. They operate within the running application, often by instrumenting the code with agents or sensors. These agents monitor the application's behavior in real-time during manual or automated tests (e.g., QA tests). This "gray-box" approach allows them to analyze code execution, data flow, and control flow from within, providing precise details about vulnerabilities, including the specific line of code responsible.
When they are used: During functional testing, quality assurance (QA), or continuous testing in development or test environments.
Pros:
High accuracy and low false positives due to real-time analysis within the application's context.
Provides detailed remediation guidance, including the exact location in the code.
Can detect vulnerabilities that neither SAST nor DAST might find alone.
Easily integrates into existing CI/CD pipelines and testing frameworks.
Cons:
Requires the application to be running and undergoing testing.
May have performance overhead due to instrumentation.
Can require setup and configuration within the application environment.
Examples: Contrast Security, HCL AppScan, Veracode.
4. Software Composition Analysis (SCA) Tools
How they work: Modern applications heavily use open-source and third-party components (libraries, frameworks, etc.). SCA tools scan an application's codebase to identify all such elements, their versions, and associated dependencies. They then compare this inventory against databases of known vulnerabilities (e.g., CVEs - Common Vulnerabilities and Exposures) and licensing risks. SCA tools generate a "Software Bill of Materials" (SBOM) that lists all included components.
When they are used: Throughout the SDLC, from initial development to deployment, to continuously monitor for new vulnerabilities in dependencies.
Pros:
Addresses a critical attack surface: vulnerabilities in third-party code.
Helps manage licensing compliance for open-source components.
Provides actionable remediation advice for known vulnerable components.
Cons:
Only identifies vulnerabilities in known, public components, not custom code.
May require significant effort to manage and update dependencies.
Examples: Black Duck (Synopsys), Mend.io (formerly WhiteSource), Snyk, OWASP Dependency-Check.
5. Runtime Application Self-Protection (RASP) Tools
How they work: RASP tools are embedded directly into the application or its runtime environment. They actively monitor the application's behavior and incoming traffic in real-time, detecting and blocking attacks as they occur. Unlike WAFs (Web Application Firewalls) that sit outside the application, RASP has deep visibility into its internal logic and data flow, allowing it to provide more precise and context-aware protection. If an attack attempt is detected, RASP can prevent it by terminating the session, issuing alerts, or sanitizing inputs.
When they are used: Primarily in production environments to provide continuous protection.
Pros:
Provides real-time, in-application protection against known and zero-day attacks.
Low false positives because it understands the application's internal state.
Can protect against attacks that bypass traditional perimeter defenses.
Cons:
Can introduce some performance overhead.
Requires integration within the application itself.
More of a protection mechanism than a testing tool for finding vulnerabilities during development, though it does detect exploitation attempts.
Examples: Imperva RASP, Contrast Protect.
Other Important AST Considerations:
Mobile Application Security Testing (MAST): Tools specifically designed to find vulnerabilities unique to mobile platforms (iOS, Android), including insecure data storage, weak encryption, and issues related to mobile device functionalities.
API Security Testing: Focuses on securing Application Programming Interfaces (APIs) that applications use and expose. This involves testing for common API vulnerabilities like broken authentication, improper authorization, and excessive data exposure.
Container Security Testing: Analyzes containers (like Docker images) for vulnerabilities, misconfigurations, and adherence to security best practices.
Cloud Security Testing: Addresses security issues specific to cloud-native applications and infrastructure, including misconfigurations in cloud deployments and serverless functions.
Penetration Testing (Pen Testing): While not exclusively an automated "tool," penetration testing involves ethical hackers manually simulating real-world attacks to find and exploit vulnerabilities that automated tools might miss. Tools like Metasploit are often used in penetration testing.
By combining these different Application Security Testing tools and methodologies, organizations can establish a comprehensive security posture for their applications, identifying and mitigating risks across the entire software development lifecycle and into production.
ThreatNG, an all-in-one external attack surface management, digital risk protection, and security ratings solution, provides robust capabilities that significantly assist with Application Security Testing (AST) by focusing on external, unauthenticated perspectives of an organization's digital assets. ThreatNG's strengths lie in its ability to identify and assess externally visible and exploitable risks, complementing a holistic AST strategy.
How ThreatNG Helps with Application Security Testing Tools
ThreatNG's approach to AST is primarily through its external discovery and assessment capabilities, which simulate an attacker's view to uncover vulnerabilities and misconfigurations that could impact web applications, APIs, mobile apps, and underlying infrastructure.
ThreatNG performs purely external, unauthenticated discovery, meaning it identifies assets without needing any internal access or connectors. This is crucial for AST as it mirrors how an attacker initially probes an organization's publicly accessible applications.
Examples: ThreatNG can discover web applications, associated subdomains, cloud services, and mobile applications exposed to the internet. This external inventory forms the basis for subsequent security assessments, ensuring that all outward-facing application components are considered for security vulnerabilities. For instance, it might discover a new marketing subdomain (e.g.,
promo.example.com) that hosts an outdated web application, which traditional internal AST tools might miss if not explicitly included in their scan scope.
ThreatNG provides a comprehensive suite of assessment ratings that directly inform AST efforts by highlighting external weaknesses.
Web Application Hijack Susceptibility: This score is substantiated by analyzing external attack surface and digital risk intelligence, including Domain Intelligence, to identify potential entry points for attackers on a web application.
Example: ThreatNG might identify that a web application lacks proper security headers or is susceptible to clickjacking, increasing its hijack susceptibility. This information guides DAST tools to specifically test for these header-related vulnerabilities or helps security teams prioritize hardening configurations.
Subdomain Takeover Susceptibility: ThreatNG evaluates this by incorporating Domain Intelligence, which includes analysis of subdomains, DNS records, and SSL certificate statuses.
Example: ThreatNG could detect a dangling DNS record pointing to a de-provisioned cloud resource, making a subdomain vulnerable to takeover. While not directly an application code issue, a subdomain takeover can lead to defacement, phishing, or content injection, directly impacting the integrity and trustworthiness of applications hosted under that domain.
BEC & Phishing Susceptibility: Derived from Domain Intelligence (DNS Intelligence, Domain Name Permutations, Web3 Domains, Email Intelligence) and Dark Web Presence.
Example: ThreatNG might find that an organization's email security presence (DMARC, SPF, DKIM records) is weak or that compromised employee credentials are found on the dark web. While not a direct application vulnerability, these findings indicate a heightened risk of phishing attacks that could target application users, leading to compromised accounts.
Brand Damage Susceptibility: Derived from attack surface and digital risk intelligence, ESG Violations, Sentiment and Financials, and Domain Intelligence.
Example: If ThreatNG identifies negative news about a data breach related to a particular application, it directly contributes to the brand damage susceptibility score. This prompts a deeper dive into the application's security.
Data Leak Susceptibility: Based on Cloud and SaaS Exposure, Dark Web Presence (Compromised Credentials), Domain Intelligence (DNS Intelligence, Email Intelligence), and Sentiment and Financials.
Example: ThreatNG could discover an openly exposed AWS S3 bucket associated with an application storing sensitive user data. This directly indicates a critical data leak vulnerability that needs immediate remediation from an AST perspective.
Cyber Risk Exposure: Considers Domain Intelligence parameters like certificates, subdomain headers, vulnerabilities, and sensitive ports. Code Secret Exposure and compromised credentials on the dark web are also factored in.
Example: ThreatNG might flag an application's server exposing sensitive ports (e.g., an unauthenticated database port) or having outdated SSL certificates, increasing its cyber risk exposure. It can also detect exposed code repositories containing hardcoded API keys or other secrets, which is a direct application security flaw.
Cloud and SaaS Exposure: Evaluates cloud services and SaaS solutions for impersonations or open exposed buckets.
Example: ThreatNG can identify if an organization has misconfigured cloud services (e.g., an unauthenticated cloud database instance backing a web application) or if employees are using unsanctioned SaaS applications that could pose a risk. This directly points to cloud-related security vulnerabilities that affect applications hosted or interacting with these services.
ESG Exposure: Rates an organization based on discovered environmental, social, and governance (ESG) violations through its external attack surface and digital risk intelligence.
Example: While less direct for AST, if ThreatNG uncovers a history of compliance violations related to data privacy, it could indicate underlying systemic issues in how applications handle sensitive data, prompting a review of the application's data protection mechanisms.
Supply Chain & Third Party Exposure: Derived from Domain Intelligence (enumerating vendor technologies from DNS and subdomains), Technology Stack, and Cloud and SaaS Exposure.
Example: ThreatNG might identify an application using a vulnerable version of a third-party JavaScript library or relying on a cloud service provider with known security issues. This directly informs SCA efforts to prioritize patching or replacing vulnerable components.
Breach & Ransomware Susceptibility: Based on exposed sensitive ports, exposed private IPs, known vulnerabilities, compromised credentials, and ransomware events.
Example: If ThreatNG identifies known vulnerabilities in an application's underlying server or critical exposed ports, it directly increases the breach susceptibility score. This prioritizes AST efforts on those specific applications.
Mobile App Exposure: Evaluates how exposed an organization’s mobile apps are through discovery in marketplaces and by checking for exposed access credentials, security credentials, and platform-specific identifiers within them.
Example: ThreatNG can discover if a mobile application in app stores contains hardcoded API keys, private keys, or other sensitive credentials, which are direct application security flaws. This is critical for Mobile AST, providing actionable intelligence on what to secure or remove from the app immediately.
3. Reporting:
ThreatNG offers various reports, including Executive, Technical, Prioritized (High, Medium, Low, and Informational), Security Ratings, Inventory, Ransomware Susceptibility, and U.S. SEC Filings.
Example: A prioritized report from ThreatNG might highlight a "High" risk associated with "Code Secret Exposure" in a public GitHub repository linked to an application, detailing the specific API key found. This report informs the development team about critical secrets that must be removed from code and managed securely.
ThreatNG monitors an organization's external attack surface, digital risk, and security ratings.
Example: An organization can configure ThreatNG to continuously monitor all their publicly accessible web applications and receive real-time alerts if a new subdomain is provisioned with a vulnerable configuration or if new compromised credentials related to an application's user base appear on the dark web. This ensures ongoing awareness of emerging external risks impacting applications.
ThreatNG offers detailed investigation modules to help users understand discovery and assessment results.
Domain Intelligence: Provides an overview of digital presence, DNS analysis (IP identification, vendors, technology), domain name permutations, Web3 domains, email intelligence (security presence, format prediction, harvested emails), and WHOIS information.
Example: Using DNS Intelligence, ThreatNG might reveal that an application's domain points to a server with an outdated operating system (via technology identification). This doesn't directly mean the application code is vulnerable, but it highlights a critical underlying infrastructure vulnerability that SAST or DAST might then target.
Subdomain Intelligence: Includes HTTP responses, header analysis, server headers, cloud hosting, website builders, e-commerce platforms, CMS, code repositories, sensitive ports (including IoT/OT, ICS, databases, remote access services), known vulnerabilities, and WAF discovery.
Example: This module could identify that a specific application subdomain is hosted on a cloud platform with exposed sensitive ports (e.g., an open database port), indicating a potential direct attack vector for the application. It could also reveal that an application uses an older, vulnerable version of WordPress as its CMS, prompting a targeted review by DAST or a patch by the development team.
Sensitive Code Exposure: Discovers public code repositories and investigates their contents for sensitive data, such as access credentials (API keys, tokens), security credentials (private keys), configuration files, and database exposures.
Example: ThreatNG might find an organization's public GitHub repository containing a
config.phpfile with hardcoded database credentials for a production application. This is a severe application security flaw directly exposed by ThreatNG, requiring immediate credential rotation and secure configuration management.
Mobile Application Discovery: Discovers mobile apps in marketplaces and checks for the presence of access credentials, security credentials, and platform-specific identifiers within them.
Example: ThreatNG could identify that a banking mobile app in Google Play contains an embedded AWS Access Key ID. This is a critical mobile application security vulnerability that ThreatNG's external analysis immediately surfaces.
Search Engine Exploitation: Helps investigate an organization’s susceptibility to exposing errors, sensitive information, public passwords, susceptible files/servers, and user data via search engines.
Example: ThreatNG might find that Google's search index contains directory listings for sensitive application folders that were not excluded adequately by
robots.txt. This indicates a potential information disclosure vulnerability related to the web application.
Cloud and SaaS Exposure: Identifies sanctioned/unsanctioned cloud services, impersonations, and open exposed cloud buckets, along with SaaS implementations.
Example: ThreatNG could highlight that an organization has an unauthenticated AWS S3 bucket accessible publicly, potentially containing application backups or sensitive static content. This is a critical cloud security misconfiguration directly impacting application data.
Online Sharing Exposure: Detects organizational entity presence within online code-sharing platforms like Pastebin or GitHub Gist.
Example: ThreatNG might find a Pastebin entry with leaked credentials or proprietary code snippets related to a specific application, indicating a potential compromise or accidental exposure.
6. Intelligence Repositories (DarCache):
ThreatNG maintains continuously updated intelligence repositories that enrich its findings and provide critical context for AST.
Vulnerabilities (DarCache Vulnerability): Provides NVD (Attack Complexity, Impact Scores, CVSS), EPSS (likelihood of exploitation), and KEV (actively exploited vulnerabilities) data, along with verified Proof-of-Concept (PoC) exploits.
Example: If ThreatNG identifies an exposed web server running an outdated version of Apache (via Subdomain Intelligence) that has a known vulnerability listed in DarCache NVD with a high EPSS score and an active KEV entry, it would flag this as a critical risk for the applications hosted on that server. A verified PoC exploit in DarCache eXploit further underscores the urgency for remediation.
Complementary Solutions and Synergies with ThreatNG for AST
While ThreatNG excels at external discovery and digital risk assessment, it can be powerfully complemented by other AST solutions for a comprehensive security strategy.
ThreatNG & SAST Tools:
Synergy: ThreatNG's external discovery helps define the perimeter of applications that need static analysis. If ThreatNG identifies an organization's public code repository with sensitive code exposure, a SAST tool can then be run directly against that code to find deeper, less obvious vulnerabilities within the exposed codebase (e.g., insecure cryptographic functions, complex data flow flaws) that ThreatNG wouldn't see from an external perspective.
Example: ThreatNG detects a public GitLab repository belonging to the organization that shows a high "Code Secret Exposure". The security team then uses a SAST tool like SonarQube to scan this repository's complete source code, uncovering hardcoded credentials and potential SQL injection vulnerabilities or insecure deserialization flaws within the application logic, which ThreatNG's external view would not reveal.
ThreatNG & DAST Tools:
Synergy: ThreatNG's external assessment findings can directly inform and prioritize DAST scans. Suppose ThreatNG flags a web application as having "Web Application Hijack Susceptibility" due to missing security headers. In that case, a DAST tool can then be configured to specifically test for these header issues and other runtime vulnerabilities like XSS, CSRF, or injection flaws that are best detected by actively interacting with the running application.
Example: ThreatNG's "Subdomain Takeover Susceptibility" assessment identifies a dangling DNS record pointing to a de-provisioned Azure service used by a specific application. This prompts the DAST tool to target that application's entry points to see if any user interaction with the application could be redirected to a malicious site, or if any sensitive information could be gleaned from the misconfigured service.
ThreatNG & IAST Tools:
Synergy: ThreatNG's identification of publicly exposed application attack surfaces (e.g., newly discovered APIs or mobile apps) can guide where IAST agents should be deployed for internal, real-time vulnerability detection during functional testing.
Example: ThreatNG discovers a new mobile application released to public marketplaces and identifies it as having "Mobile App Exposure" due to potentially exposed API keys within its contents. During the QA phase, an IAST agent is integrated into the mobile app's runtime environment. As QA testers use the app, the IAST tool observes the execution paths and confirms if the exposed API key is actually being used in an insecure way, pinpointing the exact code line responsible.
ThreatNG & SCA Tools:
Synergy: ThreatNG's "Supply Chain & Third Party Exposure" and "Technology Stack" assessments provide valuable context for SCA tools. Suppose ThreatNG identifies an application using a specific third-party e-commerce platform or content management system. In that case, an SCA tool can analyze the known vulnerabilities within the software's components and libraries.
Example: ThreatNG identifies an organization's web application using WordPress as its CMS. This information is fed to an SCA tool, which then scans explicitly the WordPress installation and its plugins for known vulnerabilities in their open-source components, alerting the team to outdated or insecure library versions.
By combining ThreatNG's external perspective on risk with the deep internal analysis capabilities of SAST, DAST, IAST, and SCA tools, organizations can achieve a holistic and proactive application security posture, addressing externally visible threats and internal code-level vulnerabilities.
