CVE-2021-29040 in Liferay
Summary
by MITRE • 05/16/2021
The JSON web services in Liferay Portal 7.3.4 and earlier, and Liferay DXP 7.0 before fix pack 97, 7.1 before fix pack 20 and 7.2 before fix pack 10 may provide overly verbose error messages, which allows remote attackers to use the contents of error messages to help launch another, more focused attacks via crafted inputs.
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Analysis
by VulDB Data Team • 05/14/2025
The vulnerability identified as CVE-2021-29040 affects JSON web services within Liferay Portal and Liferay DXP versions prior to specific fix packs, representing a critical information disclosure weakness that exposes sensitive system details to remote attackers. This flaw exists in the error handling mechanisms of the JSON web services implementation, where the system provides detailed error messages containing internal system information, stack traces, and potentially sensitive data about the application's architecture and configuration. The vulnerability is particularly concerning as it enables attackers to gather intelligence that can be leveraged for subsequent exploitation attempts, making it a significant concern for organizations relying on these platforms for enterprise web services.
The technical root cause of this vulnerability stems from inadequate error message sanitization within the JSON web service endpoints. When malformed or crafted inputs are submitted to these services, the system responds with verbose error messages that contain detailed information about the internal workings of the Liferay platform, including database connection details, file paths, system configurations, and potentially other sensitive operational data. This behavior directly violates security best practices outlined in CWE-209, which addresses the issue of information exposure through error messages, and aligns with ATT&CK technique T1211 where adversaries gather information about the target system through reconnaissance activities. The overly verbose error responses provide attackers with the exact information needed to craft more sophisticated attacks against the system's known vulnerabilities.
The operational impact of this vulnerability extends beyond simple information disclosure, as it significantly lowers the barrier to successful exploitation of other potential vulnerabilities within the affected systems. Attackers can use the detailed error information to identify specific system components, understand the application's architecture, and potentially discover other weaknesses that may exist in the platform or its underlying infrastructure. This vulnerability particularly affects organizations using Liferay Portal 7.3.4 and earlier versions, as well as Liferay DXP 7.0 before fix pack 97, 7.1 before fix pack 20, and 7.2 before fix pack 10, making these systems more susceptible to targeted attacks that leverage the leaked information. The vulnerability enables a range of attack vectors including but not limited to SQL injection, cross-site scripting, and other application-level exploits that become more effective when attackers have detailed knowledge of the target system's internal structure.
Organizations affected by CVE-2021-29040 should immediately implement mitigations focused on error message standardization and sanitization across all JSON web service endpoints. The recommended approach involves configuring the application to return generic error messages to clients while logging detailed technical information securely for administrative review. This remediation strategy addresses the core issue by ensuring that error responses do not expose sensitive system information to unauthorized users. Additionally, implementing proper input validation and sanitization measures can prevent the conditions that trigger these verbose error responses. Security teams should also consider implementing web application firewalls and intrusion detection systems that can monitor for unusual error message patterns that might indicate exploitation attempts. The fix pack releases mentioned in the vulnerability description should be applied promptly to ensure complete remediation, as these updates contain the necessary code changes to prevent the information disclosure behavior that makes this vulnerability exploitable.