attack-tree.md

Attack Tree Analysis for qos-ch/logback

Objective: Compromise application using Logback by exploiting Logback vulnerabilities (Focus on High-Risk Paths).

Attack Tree Visualization

Compromise Application via Logback Exploitation (High-Risk Paths) ├───[AND] Exploit Logback Configuration Vulnerabilities │ └───[OR] Default Configuration Vulnerabilities [HIGH RISK PATH] │ └── [CRITICAL NODE] Application uses outdated Logback version with known default configuration vulnerabilities ├───[AND] Exploit Logback Layout/Formatting Vulnerabilities │ ├───[OR] JNDI Injection via Layout Patterns (Similar to Log4Shell, potential but less likely in recent Logback versions) [HIGH RISK PATH] │ │ ├── [CRITICAL NODE] Application uses vulnerable Logback version (older versions might be susceptible) │ │ ├── Logback configuration uses layout patterns that process user-controlled input without proper sanitization [CRITICAL NODE] │ └───[OR] Custom Layout/Appender Vulnerabilities [HIGH RISK PATH] │ ├── [CRITICAL NODE] Application uses custom Layout or Appender implementations │ ├── [CRITICAL NODE] Custom implementation contains vulnerabilities (e.g., insecure deserialization, command injection, path traversal) ├───[AND] Exploit Logged Data Vulnerabilities (Indirectly via Logback, more about application logging practices) [HIGH RISK PATH] │ ├───[OR] Information Disclosure via Logs [HIGH RISK PATH] │ │ └── [CRITICAL NODE] Application logs sensitive information (e.g., passwords, API keys, PII, session tokens) │ └───[OR] Log Injection leading to other vulnerabilities (e.g., Log Analysis System Exploitation) [HIGH RISK PATH] │ │ └── [CRITICAL NODE] Application logs user-controlled input without proper sanitization

Attack Tree Path: Default Configuration Vulnerabilities

• Critical Node: Application uses outdated Logback version with known default configuration vulnerabilities
  • Attack Vector: Attackers target applications using older, unpatched versions of Logback. These versions may contain default configurations that are inherently insecure or have known vulnerabilities. For example, older versions might have less restrictive default settings or might be susceptible to vulnerabilities discovered later and patched in newer releases.
  • Impact: The impact depends on the specific vulnerability in the outdated version. It could range from information disclosure, denial of service (DoS), to potentially remote code execution (RCE) if a default configuration flaw allows for exploitation.
  • Why High-Risk: Using outdated software is a common vulnerability. Publicly known vulnerabilities in older versions are easily exploitable with readily available tools and scripts, requiring low attacker effort and skill. Detection is easy for attackers as version information is often exposed.

Attack Tree Path: JNDI Injection via Layout Patterns

• Critical Node: Application uses vulnerable Logback version (older versions might be susceptible)

  • Attack Vector: This path is reminiscent of the Log4Shell vulnerability. Older versions of Logback, or specific configurations in any version, might be vulnerable to JNDI injection if layout patterns process user-controlled input and allow for JNDI lookups (e.g., using ${jndi:}).
  • Impact: If exploitable, this can lead to Critical impact: Remote Code Execution (RCE). Attackers can inject malicious JNDI lookup strings into log messages. When Logback processes these messages, it can trigger JNDI lookups to attacker-controlled servers, leading to code execution on the application server.
  • Why High-Risk: RCE is the most severe impact. While recent Logback versions have mitigations, older systems remain vulnerable. The exploit can be relatively easy to execute if the vulnerability exists, and the impact is catastrophic.

• Critical Node: Logback configuration uses layout patterns that process user-controlled input without proper sanitization

  • Attack Vector: Even in newer Logback versions, if the configuration uses layout patterns that directly incorporate user-controlled input without sanitization, it can become vulnerable to injection attacks. If these patterns are then processed in a way that allows for interpretation of special characters or commands (like JNDI lookups in older versions or other potential injection points in future vulnerabilities), it creates an attack surface.
  • Impact: The impact depends on the specific vulnerability that can be triggered by the unsanitized input in the layout pattern. In the context of JNDI injection (older versions), it's RCE. In other scenarios, it could be information disclosure or other forms of exploitation depending on how the layout pattern is processed.
  • Why High-Risk: Logging user input is a common practice, and overlooking sanitization in layout patterns is a potential oversight. If a vulnerability exists in how these patterns are processed, it can be easily exploited by injecting malicious input.

Attack Tree Path: Custom Layout/Appender Vulnerabilities

• Critical Node: Application uses custom Layout or Appender implementations

  • Attack Vector: When developers extend Logback by creating custom Layout or Appender components, they introduce new code into the logging pipeline. If these custom components are not developed with security in mind, they can contain vulnerabilities.
  • Impact: The impact is highly variable and depends entirely on the nature of the vulnerability in the custom code. It could range from low impact (minor information disclosure) to Critical impact (RCE) if the custom component has flaws like insecure deserialization, command injection, path traversal, or other code execution vulnerabilities.
  • Why High-Risk: Custom code is inherently more prone to vulnerabilities than well-vetted, widely used libraries. Security testing and code review of custom components are often less rigorous than for core libraries, increasing the likelihood of vulnerabilities slipping through.

• Critical Node: Custom implementation contains vulnerabilities (e.g., insecure deserialization, command injection, path traversal)

  • Attack Vector: This node specifies the type of vulnerabilities that might be present in custom Layouts or Appenders. Examples include:
    • Insecure Deserialization: If the custom component deserializes data from logs or external sources without proper validation, it can be exploited to execute arbitrary code.
    • Command Injection: If the custom component executes system commands based on log data or configuration, improper input sanitization can lead to command injection.
    • Path Traversal: If the custom component handles file paths based on log data or configuration, vulnerabilities can allow attackers to access files outside of intended directories.
  • Impact: Again, the impact depends on the specific vulnerability. Insecure deserialization and command injection often lead to RCE. Path traversal can lead to information disclosure or DoS.
  • Why High-Risk: These types of vulnerabilities are common in custom code, especially when developers are not security experts. Exploiting them can have severe consequences.

Attack Tree Path: Information Disclosure via Logs

• Critical Node: Application logs sensitive information (e.g., passwords, API keys, PII, session tokens)
  • Attack Vector: This is a fundamental application security flaw. Developers may unintentionally or carelessly log sensitive data directly into log files. If these log files are accessible to attackers (due to weak access controls, compromised systems, or exposed log management systems), the sensitive information is compromised.
  • Impact: High impact: Data breach, compliance violations (GDPR, HIPAA, etc.), identity theft, account compromise, and potential for further attacks using the disclosed credentials or sensitive data.
  • Why High-Risk: Logging sensitive data is a very common mistake. The likelihood is high because it's often an oversight in development. The impact is also high due to the direct exposure of sensitive information. Detection for attackers is easy if they gain access to logs.

Attack Tree Path: Log Injection leading to other vulnerabilities

• Critical Node: Application logs user-controlled input without proper sanitization
  • Attack Vector: Similar to the layout pattern issue, if applications log user-controlled input without sanitization, attackers can inject malicious data into log messages. This injected data is not directly exploiting Logback itself, but rather using Logback as a vector to attack other systems that process these logs, such as log analysis systems (ELK, Splunk, etc.).
  • Impact: The immediate impact is usually on the log analysis system. It could lead to compromise of the log analysis system itself (e.g., command injection in dashboards, script injection), denial of service of logging/monitoring, or potentially pivoting back to the application or infrastructure if the log analysis system is connected to other systems.
  • Why High-Risk: Logging user input is common. Forgetting to sanitize this input before logging is a frequent oversight. While not directly compromising the application via Logback vulnerabilities, it uses Logback as an attack vector to compromise related infrastructure, which can indirectly impact the application and its security posture.