CVE-2021-43271 in AppResponse
Summary
by MITRE • 06/04/2022
Riverbed AppResponse 11.8.0, 11.8.5, 11.8.5a, 11.9.0, 11.9.0a, 11.10.0, 11.11.0, 11.11.0a, 11.11.1, 11.11.1a, 11.11.5, and 11.11.5a (when configured to use local, RADIUS, or TACACS authentication) logs usernames and passwords if either is entered incorrectly. If a user enters an incorrect username and/or password when logging into the WebUI, these attempted credentials are included in an error message that is logged in the WebUI log file. A log entry does not appear if the username and password provided correctly match a valid set of credentials. This also does not happen if AppResponse is configured to use SAML authentication. The WebUI log file is included in subsequent diagnostic system dumps that are generated. (Only users with Full Control access to the System Configuration permission can generate system dumps. By default, only System Administrators have Full Control access to the System Configuration permission.)
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Analysis
by VulDB Data Team • 06/08/2022
This vulnerability exists in Riverbed AppResponse versions ranging from 11.8.0 through 11.11.5a when configured with local, RADIUS, or TACACS authentication mechanisms. The flaw represents a critical security oversight where the system inadvertently logs authentication credentials in cleartext format within error messages when login attempts fail. This behavior directly violates fundamental security principles and creates a significant risk vector for unauthorized access. The vulnerability is classified under CWE-532, which specifically addresses information exposure through log files, making it a direct descendant of well-established information disclosure patterns. The technical implementation flaw occurs at the authentication handler level where error messages are constructed without proper sanitization of credential data, allowing sensitive information to persist in system logs.
The operational impact of this vulnerability extends beyond simple credential exposure, creating a comprehensive attack surface that can be exploited by malicious actors with access to system diagnostic information. When users enter incorrect credentials during web interface authentication, the system generates error messages containing both the username and password in plaintext format within the WebUI log file. This logging behavior occurs exclusively during failed authentication attempts and does not manifest when valid credentials are provided, creating a false sense of security for legitimate users. The vulnerability affects all versions mentioned, indicating a persistent flaw in the application's authentication logging mechanism that spans multiple releases and suggests inadequate security testing during development cycles. The log files containing this sensitive information are automatically included in system diagnostic dumps, which are accessible to users with Full Control access to System Configuration permissions, typically limited to system administrators.
The security implications of this vulnerability align with ATT&CK technique T1078.004, which covers legitimate credentials and default credentials, as attackers can leverage these exposed credentials to gain unauthorized access to the system. The vulnerability also maps to CWE-312, which addresses cleartext storage of sensitive information, and CWE-200, which addresses information exposure. The fact that this vulnerability only occurs with local, RADIUS, or TACACS authentication mechanisms while being absent in SAML configurations suggests that the authentication module's logging behavior is inconsistent across different authentication types, indicating poor security design patterns. System dumps containing these log files can be generated by users with specific permissions, creating a potential insider threat vector where authorized personnel might inadvertently expose sensitive information. The default configuration that limits dump generation to System Administrators provides some protection but does not eliminate the risk entirely, as administrative accounts themselves can be compromised through various attack vectors.
Mitigation strategies should focus on immediate remediation through vendor-provided patches or updates, as the vulnerability requires software-level fixes to address the root cause. Organizations should implement immediate monitoring of system logs for suspicious credential exposure patterns and establish procedures to rotate compromised credentials. The recommended approach involves disabling unnecessary authentication methods, implementing additional logging controls to sanitize credential information, and ensuring that system diagnostic dumps are handled with appropriate access controls. Network segmentation and privileged access management should be enhanced to limit who can generate system dumps, while regular security audits should verify that no credential information is being logged in plaintext format. Additionally, organizations should consider implementing automated log analysis tools that can detect and alert on credential exposure patterns, providing proactive defense against this type of information disclosure vulnerability. The vulnerability demonstrates the critical importance of proper input sanitization and output encoding in security-sensitive applications, particularly those handling authentication data.