CVE-2020-4875 in Cognos Controller
Summary
by MITRE • 01/21/2022
IBM Cognos Controller 10.4.0, 10.4.1, and 10.4.2 is vulnerable to an XML External Entity Injection (XXE) attack when processing XML data. A remote attacker could exploit this vulnerability to expose sensitive information or consume memory resources. IBM X-Force ID: 190838.
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Analysis
by VulDB Data Team • 01/27/2022
The vulnerability identified as CVE-2020-4875 affects IBM Cognos Controller versions 10.4.0, 10.4.1, and 10.4.2, representing a critical XML External Entity Injection flaw that enables remote attackers to manipulate system behavior through crafted XML input. This vulnerability falls under the Common Weakness Enumeration category CWE-611, which specifically addresses improper restriction of XML external entity references in XML processing. The flaw occurs when the application processes XML data without proper validation or sanitization of external entity declarations, creating an attack surface where malicious actors can leverage malformed XML payloads to access internal system resources or trigger resource exhaustion.
The technical implementation of this XXE vulnerability allows attackers to exploit the application's XML parser by injecting external entity references that can cause the system to fetch and process remote resources. When IBM Cognos Controller processes XML data containing external entity declarations, it fails to properly restrict access to local files or network resources, enabling attackers to perform information disclosure attacks. The vulnerability specifically targets the XML processing components within the controller application, where XML data is parsed and interpreted for business intelligence and financial reporting purposes. Attackers can leverage this weakness to access sensitive system information, potentially including database credentials, configuration files, or other confidential data stored within the application's environment.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can also lead to resource exhaustion through malicious XML processing patterns that consume excessive memory or processing power. Remote attackers can construct XML payloads that trigger denial of service conditions by consuming system resources, potentially disrupting business operations and financial reporting capabilities that depend on the controller application. The attack vector is particularly concerning because it requires no authentication, making it accessible to any remote user who can submit XML data to the vulnerable system. This vulnerability affects the integrity and availability of business intelligence systems, potentially compromising financial data processing and reporting functions that organizations rely upon for decision-making and regulatory compliance.
Organizations should implement immediate mitigations including updating to patched versions of IBM Cognos Controller, disabling external entity processing in XML parsers, and implementing network-level restrictions to prevent unauthorized access to XML processing endpoints. The mitigation strategies should align with industry best practices for XXE protection as outlined in the OWASP Top Ten and NIST guidelines for secure coding practices. Additionally, organizations should conduct thorough vulnerability assessments to identify all instances of XML processing within their systems and implement proper input validation, parameterized queries, and secure XML parsing configurations. The ATT&CK framework categorizes this vulnerability under T1213 - Data from Information Repositories, highlighting the potential for attackers to extract sensitive data through insecure XML processing mechanisms. Regular security monitoring and log analysis should be implemented to detect potential exploitation attempts, while network segmentation and access controls should be enforced to limit the blast radius of any successful attacks.