attack-surface.md

Attack Surface Analysis for sirupsen/logrus

Attack Surface: Log Injection Vulnerabilities

• Description: Attackers inject malicious data into log files by exploiting unsanitized input being logged through logrus. This can lead to log manipulation and exploitation of log processing systems.
• Logrus Contribution: logrus faithfully logs whatever data it is provided. If developers use logrus to log user-controlled input or external data without proper sanitization, it directly facilitates the injection of malicious content into log files.
• Example: An application logs user input directly into a log message using logrus without sanitizing it: logrus.Infof("User input: %s", userInput). If userInput contains format string specifiers (e.g., %n, %x) or control characters, these will be interpreted by log processing tools or potentially exploited in downstream systems that consume the logs. Injected scripts or malicious commands could be embedded within logs and executed by vulnerable log analysis tools.
• Impact:
  • Log Forgery and Tampering: Attackers can manipulate log entries to hide malicious activity or frame others.
  • Exploitation of Log Processing Systems: Malicious log entries can be crafted to exploit vulnerabilities in SIEM systems, log aggregators, or other tools that process logs, potentially leading to command injection or other severe consequences within these systems.
  • Compromised Audit Trails: Injected data can corrupt audit logs, hindering incident response and forensic analysis.
• Risk Severity: Critical
• Mitigation Strategies:
  • Strict Input Sanitization: Sanitize all user-provided input and external data before logging with logrus. Escape format string specifiers and control characters.
  • Structured Logging with Fields: Utilize logrus's structured logging capabilities (fields) extensively. Log data as fields rather than embedding it directly into log messages. This separates data from the log message format and significantly reduces the risk of injection. Example: logrus.WithField("user_input", userInput).Info("User activity").
  • Parameterization for Log Messages: When possible, use parameterized logging where log messages are templates and data is passed as separate parameters, further isolating data from the log message structure.
  • Secure Log Processing Infrastructure: Ensure that systems processing logs are hardened against injection attacks and follow security best practices.

Attack Surface: Information Disclosure of Highly Sensitive Data through Verbose Logging

• Description: logrus is used to log highly sensitive information (like credentials, API keys, PII, security tokens) which is then exposed to unauthorized access due to insecure log storage or misconfiguration.
• Logrus Contribution: logrus's flexibility allows developers to log any data they choose. If developers mistakenly or carelessly log highly sensitive information using logrus, and if log storage is not adequately secured, logrus becomes a direct contributor to this information disclosure vulnerability.
• Example: Developers inadvertently log user passwords or API keys at Debug or Info level using logrus during development or troubleshooting. This logging level is mistakenly left enabled in production, and these sensitive logs are written to a file system accessible to unauthorized users or are transmitted over unencrypted channels to a logging server.
• Impact:
  • Exposure of Critical Credentials: Direct exposure of passwords, API keys, or security tokens can lead to immediate and severe security breaches, including unauthorized access to systems and data.
  • Privacy Violations and Compliance Issues: Logging Personally Identifiable Information (PII) without proper safeguards and access controls can lead to privacy violations and non-compliance with regulations like GDPR or HIPAA.
  • Full System Compromise: Exposed credentials or internal system details can provide attackers with the necessary information to gain complete control over the application and underlying infrastructure.
• Risk Severity: High to Critical (Critical if credentials or critical secrets are exposed; High if sensitive PII or business secrets are exposed).
• Mitigation Strategies:
  • Absolutely Minimize Logging of Sensitive Data: Avoid logging highly sensitive information like passwords, API keys, security tokens, and critical PII. If logging such data is unavoidable for debugging in non-production environments, implement robust redaction or masking techniques before logging with logrus.
  • Enforce Strict Logging Level Controls in Production: Ensure that logging levels in production environments are set to Error, Warning, or Info at most, and that Debug and Trace levels are strictly disabled. Implement configuration management to enforce these levels consistently.
  • Secure Log Storage and Access Controls: Store logs in secure locations with restricted access permissions. Implement strong authentication and authorization mechanisms to control who can access log files.
  • Log Encryption at Rest and in Transit: Encrypt log files at rest and use secure protocols (HTTPS, TLS, SSH) for transmitting logs to external systems to protect sensitive data from unauthorized access and interception.
  • Regular Security Audits and Code Reviews: Conduct regular security audits and code reviews to identify and eliminate any instances of unintentional or unnecessary logging of sensitive information using logrus.