CVE-2024-4412 in API Manager
Summary
by MITRE • 10/19/2026
The software accepts user-supplied data without sufficient validation, allowing for the injection of malicious Expression Language (EL) code. This can lead to the execution of arbitrary operations within the affected deployment.
Exploitation of this vulnerability requires administrator privileges. The impact is minimal as EL usage is restricted to certain read operations.
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Analysis
by VulDB Data Team • 10/19/2026
The identified security flaw represents a classic instance of insecure direct object reference or improper input validation, specifically manifesting through the injection of malicious Expression Language code into software components that process user-supplied data. In many enterprise applications, particularly those built on Java-based frameworks such as Spring or Jakarta EE, Expression Language serves as a powerful mechanism for dynamically evaluating expressions within templates and configuration files. While this feature provides significant flexibility for developers to create dynamic content, it also introduces a substantial attack surface if the input is not rigorously sanitized before being passed to the expression evaluator. The vulnerability arises because the application fails to adequately validate or escape special characters that are interpreted by the EL engine as executable commands rather than literal data strings. This lack of validation allows an attacker to craft specific payloads that bypass intended logic, effectively turning a read-only interface into a vector for arbitrary code execution within the context of the running application process.
From a technical perspective, this vulnerability aligns with CWE-94, which describes Improper Control of Generation of Code or Script, often referred to as injection attacks. More specifically, it falls under the sub-category of Expression Language Injection. The core issue lies in the failure to distinguish between data and code during the parsing phase. When user input is directly interpolated into an EL expression without proper context-aware escaping, the interpreter may execute methods that were not intended for public access. This can include invoking static methods on arbitrary classes, accessing private fields via reflection, or triggering side effects through getter methods. The severity of this flaw is heavily dependent on the configuration and permissions of the underlying environment. In many secure deployments, EL execution is sandboxed to prevent such abuses, but when these safeguards are absent or misconfigured, the potential for exploitation increases significantly.
The operational impact of exploiting this vulnerability is nuanced by the specific constraints mentioned in the report: exploitation requires administrator privileges, and the functionality is restricted primarily to read operations. This limitation suggests that while an attacker with administrative access can inject malicious EL code, they cannot directly write files or execute system-level commands through this vector alone. Instead, the impact likely involves unauthorized data exfiltration, such as reading sensitive configuration files, database contents, or internal application state that should remain confidential even to administrators in certain contexts. For instance, an attacker might use injected expressions to retrieve environment variables, connection strings, or other secrets stored within the application context. This constitutes a breach of confidentiality and potentially integrity if the retrieved data is used for further attacks against other systems. The requirement for admin privileges means that this vulnerability cannot be exploited by unauthenticated external attackers, thereby reducing its risk score in standard CVSS calculations but still posing a significant threat to internal security posture and compliance requirements regarding privileged access management.
In terms of industry frameworks, this behavior maps closely to the MITRE ATT&CK technique T1059, Command and Scripting Interpreter, specifically within the context of application layer exploitation. Although direct command execution is limited, the ability to execute arbitrary expressions allows for complex data manipulation that can facilitate lateral movement or deeper reconnaissance within a compromised network segment where administrative credentials have been obtained. The vulnerability also relates to CWE-749, Exposure of Dangerous Method or Function, as it involves invoking methods through reflection-like mechanisms provided by the EL engine. Understanding these mappings is crucial for security teams aiming to prioritize remediation efforts based on established threat models and attack patterns recognized globally.
To mitigate this risk, developers must implement strict input validation strategies that adhere to the principle of least privilege and defense in depth. The most effective mitigation involves avoiding the direct use of user-supplied data within Expression Language expressions whenever possible. If dynamic evaluation is necessary, inputs should be validated against a whitelist of allowed characters or patterns rather than relying on blacklist approaches which are prone to bypasses. Additionally, enabling strict EL configuration settings that disable access to dangerous classes and methods can significantly reduce the impact of any successful injection attempt. For example, configuring the ExpressionFactory to restrict reflective calls ensures that even if malicious code is injected, it cannot interact with sensitive system resources. Regular security audits and static application security testing tools configured to detect unsafe EL usage patterns are also recommended practices to identify and remediate such vulnerabilities before deployment into production environments.