CVE-2016-9023 in Exponent
Summary
by MITRE • 12/31/2020
Exponent CMS before 2.6.0 has improper input validation in cron/find_help.php.
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Analysis
by VulDB Data Team • 12/31/2020
The vulnerability identified in Exponent CMS versions prior to 2.6.0 represents a critical security flaw in the cron/find_help.php script that demonstrates poor input validation practices. This issue falls under the category of CWE-20, which specifically addresses improper input validation, making it a fundamental weakness in the application's security architecture. The vulnerability occurs within the cron job execution functionality where user-supplied parameters are not adequately sanitized or validated before being processed by the system.
The technical flaw manifests when the cron/find_help.php endpoint receives input parameters that should be strictly controlled but instead allows arbitrary data to be passed through without proper verification. This lack of input sanitization creates multiple attack vectors including potential command injection, cross-site scripting, and other malicious payload execution scenarios. The vulnerability is particularly concerning because it operates within the cron job framework, which typically runs with elevated privileges and system access rights, potentially allowing attackers to escalate their privileges or execute arbitrary code on the server.
The operational impact of this vulnerability extends beyond simple data corruption or unauthorized access. Attackers who can exploit this flaw may gain the ability to execute malicious commands on the target system, potentially leading to full system compromise. The cron job context means that even if the initial exploitation is limited, the elevated permissions associated with scheduled tasks could provide attackers with persistent access or the ability to modify critical system components. This vulnerability also aligns with ATT&CK technique T1059.001 for command and scripting interpreter, as it could enable adversaries to execute commands through the vulnerable input handling mechanism.
The implications of this vulnerability are particularly severe in environments where Exponent CMS is deployed with administrative privileges or where the cron jobs have access to sensitive system resources. Organizations running affected versions should immediately consider implementing temporary mitigations such as disabling unnecessary cron jobs, restricting network access to the vulnerable endpoint, and monitoring for suspicious activity patterns. The fix requires proper input validation implementation that includes whitelisting acceptable parameter values, implementing strict type checking, and ensuring all user-supplied data is properly escaped or sanitized before processing.
Security professionals should note that this vulnerability demonstrates the critical importance of validating all inputs at multiple layers within application architecture. The weakness in the cron/find_help.php script represents a failure in defense-in-depth principles where proper input validation should occur regardless of the execution context. Organizations should also consider implementing web application firewalls to detect and block malicious input patterns, while conducting comprehensive security assessments to identify similar input validation issues across their entire application portfolio.
The remediation process for this vulnerability requires updating to Exponent CMS version 2.6.0 or later where proper input validation has been implemented in the affected script. Additionally, organizations should implement regular security audits of their custom cron jobs and scheduled tasks to ensure that all input handling follows secure coding practices. The fix should include comprehensive parameter validation, proper error handling for malformed inputs, and logging mechanisms to track suspicious activities. This vulnerability also highlights the importance of keeping CMS platforms updated and the risks associated with running outdated software versions in production environments.
This type of vulnerability commonly appears in content management systems where cron jobs are used for automated maintenance tasks but lack proper security controls around input processing. The attack surface expands significantly when these automated processes can be influenced by user input, creating opportunities for attackers to manipulate system behavior through carefully crafted parameters. Organizations should also implement monitoring solutions that can detect unusual patterns in cron job execution or unexpected parameter values that might indicate exploitation attempts. The vulnerability serves as a reminder that automated systems are not immune to security flaws and require the same rigorous input validation and access control measures as interactive application components.
The broader implications of this vulnerability extend to industry compliance requirements where proper input validation is often mandated for secure software development practices. Organizations should review their existing security controls to ensure that all automated processes, particularly those with elevated privileges, follow established security frameworks such as OWASP Top Ten or NIST cybersecurity guidelines. The vulnerability also underscores the need for regular security training for developers to understand proper input validation techniques and avoid common pitfalls in application design that can lead to exploitable weaknesses.