CVE-2021-22133 in Elastic APM Agent for Go
Summary
by MITRE • 02/11/2021
The Elastic APM agent for Go versions before 1.11.0 can leak sensitive HTTP header information when logging the details during an application panic. Normally, the APM agent will sanitize sensitive HTTP header details before sending the information to the APM server. During an application panic it is possible the headers will not be sanitized before being sent.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 02/27/2021
The vulnerability identified as CVE-2021-22133 affects the Elastic APM agent for Go versions prior to 1.11.0, representing a critical security flaw that compromises the confidentiality of sensitive data during application failure scenarios. This issue specifically manifests when an application experiences a panic condition, which is a runtime error that causes the program to terminate abruptly. The Elastic APM agent is designed to monitor and report application performance metrics, including HTTP request details, to help developers identify and resolve issues in their applications. The agent's primary function involves collecting telemetry data and transmitting it to an APM server for analysis and visualization purposes.
The technical flaw stems from inconsistent sanitization practices within the agent's logging mechanism. Under normal operating conditions, the Elastic APM agent implements proper data sanitization procedures that prevent sensitive HTTP header information from being transmitted to the APM server. This sanitization process typically involves removing or obfuscating fields containing authentication tokens, session identifiers, personal identification information, and other confidential data that could compromise user privacy or system security. However, during application panic events, the agent fails to apply these same sanitization protocols to HTTP headers, creating a potential data exposure channel.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can provide attackers with access to sensitive session data, authentication tokens, and other confidential information that may be present in HTTP headers. This exposure occurs specifically during panic conditions when the application terminates unexpectedly, making it particularly concerning for applications handling sensitive user data or operating in regulated environments. The vulnerability creates a window of opportunity for malicious actors to intercept and exploit this leaked information, potentially leading to unauthorized access to user accounts, data breaches, or other security incidents that could compromise the integrity of the affected systems.
The flaw aligns with CWE-200, which addresses "Information Exposure," and represents a specific instance where sensitive data is unintentionally exposed during error handling scenarios. From an ATT&CK framework perspective, this vulnerability maps to T1566, "Phishing," and T1071.004, "Application Layer Protocol: DNS," as attackers could potentially leverage leaked header information to craft more sophisticated phishing attacks or use the exposed credentials for further exploitation. The vulnerability also relates to T1580, "Taint Data", where sensitive information is inadvertently introduced into logs or monitoring systems. Organizations using the affected Elastic APM agent versions should immediately implement the available patch updates to 1.11.0 or later, which corrects the sanitization behavior during panic conditions. Additionally, system administrators should review their monitoring configurations to ensure that no sensitive data is being inadvertently exposed through other logging mechanisms and consider implementing additional network monitoring to detect potential data leakage patterns. The vulnerability demonstrates the critical importance of maintaining consistent security practices across all application states, including error handling and termination conditions, to prevent data exposure during unexpected program behavior.