CVE-2024-51466 Overview
IBM Cognos Analytics is vulnerable to an Expression Language (EL) Injection vulnerability that affects versions 11.2.0 through 11.2.4 FP4 and 12.0.0 through 12.0.4. A remote attacker could exploit this vulnerability to expose sensitive information, consume memory resources, and/or cause the server to crash when using a specially crafted EL statement. This vulnerability is classified under CWE-917 (Improper Neutralization of Special Elements used in an Expression Language Statement).
Critical Impact
This vulnerability allows unauthenticated remote attackers to exploit Expression Language injection to achieve information disclosure, memory exhaustion, and denial of service conditions on affected IBM Cognos Analytics servers.
Affected Products
- IBM Cognos Analytics 11.2.0 through 11.2.4 FP4
- IBM Cognos Analytics 12.0.0 through 12.0.4
- IBM Cognos Analytics 11.2.4 (including Fixpack 1 through Fixpack 4)
Discovery Timeline
- 2024-12-20 - CVE-2024-51466 published to NVD
- 2025-07-02 - Last updated in NVD database
Technical Details for CVE-2024-51466
Vulnerability Analysis
Expression Language (EL) Injection vulnerabilities occur when user-controlled input is improperly embedded into EL expressions without adequate sanitization. In the context of IBM Cognos Analytics, the application fails to properly neutralize special elements within user-supplied input before incorporating it into Expression Language statements. This allows attackers to manipulate the EL evaluation context to execute arbitrary expressions.
The vulnerability is network-accessible, meaning attackers can exploit it remotely without requiring any authentication or user interaction. However, exploitation complexity is high, indicating that specific conditions must be met for successful exploitation. When successfully exploited, the impact spans confidentiality, integrity, and availability—attackers can extract sensitive data, potentially modify application behavior, and crash the server through resource exhaustion.
Root Cause
The root cause of CVE-2024-51466 lies in improper input validation and neutralization of special characters used in Expression Language statements (CWE-917). IBM Cognos Analytics processes user-supplied input within EL contexts without sufficiently sanitizing or escaping EL-specific syntax elements such as ${...} or #{...} delimiters. This allows malicious payloads to break out of the intended data context and be interpreted as executable EL expressions by the underlying expression evaluator.
Attack Vector
The attack vector for this vulnerability is network-based, allowing remote exploitation. An attacker can craft malicious HTTP requests containing specially constructed Expression Language payloads targeting vulnerable endpoints within IBM Cognos Analytics. These payloads can include:
Information Disclosure Payloads - EL expressions designed to access and exfiltrate sensitive server-side objects, environment variables, configuration data, or internal application state.
Resource Exhaustion Payloads - EL expressions that trigger computationally expensive operations, recursive evaluations, or memory allocation loops to exhaust server resources.
Denial of Service Payloads - EL expressions that cause unhandled exceptions, null pointer dereferences, or infinite loops leading to server crashes.
The exploitation mechanism involves injecting EL syntax within request parameters or input fields that are subsequently processed by the application's expression evaluator. Technical details regarding specific exploitation techniques can be found in the IBM Security Advisory.
Detection Methods for CVE-2024-51466
Indicators of Compromise
- Unusual HTTP requests containing Expression Language syntax patterns such as ${...} or #{...} in URL parameters, headers, or request bodies
- Abnormal memory consumption or CPU utilization spikes on Cognos Analytics servers
- Server crash events or service restarts without scheduled maintenance
- Error logs containing EL evaluation exceptions or stack traces referencing expression language parsers
Detection Strategies
- Implement Web Application Firewall (WAF) rules to detect and block requests containing EL injection patterns such as ${, #{, T(, or .getClass()
- Monitor application logs for expression evaluation errors, unauthorized object access attempts, or unusual evaluation contexts
- Deploy network intrusion detection signatures targeting known EL injection payload patterns
- Enable verbose logging on Cognos Analytics to capture detailed request information for forensic analysis
Monitoring Recommendations
- Establish baseline metrics for server memory and CPU utilization to detect anomalous resource consumption patterns
- Configure alerting for Cognos Analytics service availability and automatic restart events
- Implement real-time log analysis to detect patterns consistent with EL injection reconnaissance or exploitation
- Monitor for outbound connections from Cognos servers that may indicate data exfiltration following successful exploitation
How to Mitigate CVE-2024-51466
Immediate Actions Required
- Review the IBM Security Advisory for specific patch and remediation guidance
- Inventory all IBM Cognos Analytics deployments and identify instances running vulnerable versions (11.2.0 through 11.2.4 FP4 and 12.0.0 through 12.0.4)
- Prioritize patching externally-facing Cognos Analytics instances due to the network-based attack vector
- Implement network segmentation to limit exposure of Cognos Analytics servers to untrusted networks
Patch Information
IBM has released security updates to address this vulnerability. Organizations should apply the latest available patches for their respective IBM Cognos Analytics versions. Detailed patch information and download links are available through the IBM Support Page. It is recommended to upgrade to version 11.2.4 FP5 or later for the 11.x branch, or 12.0.5 or later for the 12.x branch, as applicable.
Workarounds
- Deploy a Web Application Firewall (WAF) with rules configured to block common EL injection patterns in incoming requests
- Restrict network access to Cognos Analytics administrative and reporting interfaces using firewall rules and access control lists
- Consider temporarily disabling or restricting access to features that process user-supplied expressions until patches can be applied
- Implement strict input validation at the network perimeter using reverse proxy configurations to filter potentially malicious payloads
# Example WAF rule pattern for detecting EL injection attempts
# Block requests containing common EL injection patterns
# Pattern: \$\{.*\}|\#\{.*\}|\.getClass\(|\.getRuntime\(|T\([a-zA-Z]
# Apply this pattern to URL parameters, request body, and headers
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
