CVE-2019-4513 in Security Access Manager for Enterprise Single Sign-On
Summary
by MITRE
IBM Security Access Manager for Enterprise Single Sign-On 8.2.2 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: 164555.
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Analysis
by VulDB Data Team • 12/04/2023
IBM Security Access Manager for Enterprise Single Sign-On version 8.2.2 contains a critical XML External Entity Injection vulnerability that allows remote attackers to manipulate XML processing behavior. This weakness stems from the application's insufficient validation of XML input data, specifically when handling external entity references within XML documents. The vulnerability falls under CWE-611 which categorizes improper restriction of XML external entity reference processing, making it a direct descendant of the broader XXE attack surface. Attackers can exploit this flaw by submitting malicious XML content that includes references to external resources, potentially enabling information disclosure, denial of service attacks, and resource exhaustion. The vulnerability exists because the XML parser does not properly sanitize or restrict external entity resolution, allowing attackers to craft payloads that can access local files, perform server-side request forgery, or consume excessive system resources through entity expansion attacks.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass significant security risks for organizations relying on IBM Security Access Manager for their authentication infrastructure. Remote exploitation requires no authentication credentials, making the attack surface particularly dangerous for enterprise environments where single sign-on systems serve as critical access control points. Attackers can leverage this vulnerability to extract sensitive configuration data, user credentials, or system information that may lead to further compromise of the authentication ecosystem. The memory consumption aspect of this vulnerability presents additional risks including potential denial of service conditions that could disrupt legitimate authentication services. According to ATT&CK framework, this vulnerability maps to T1566.001 (Phishing via Social Engineering) and T1071.004 (Application Layer Protocol: DNS) as attackers may use the information disclosure to craft more sophisticated social engineering campaigns or establish persistent access through compromised authentication tokens.
Mitigation strategies for this XXE vulnerability should prioritize immediate patch deployment from IBM Security, as the vendor has released security fixes addressing this specific weakness. Organizations should implement XML input validation controls that disable external entity resolution entirely within the application's XML processing components. Network segmentation and firewall rules can help limit exposure by restricting access to the vulnerable application to trusted networks only. Additionally, implementing web application firewalls with XXE detection capabilities provides an additional layer of protection. Security teams should conduct thorough vulnerability assessments to identify all instances of XML processing within the application stack and ensure proper input sanitization. The remediation process should include disabling DTD processing, implementing strict XML schema validation, and monitoring for suspicious XML traffic patterns. Organizations should also consider implementing automated security scanning tools that can detect XXE vulnerabilities in their applications and establish incident response procedures for handling potential exploitation attempts. Regular security testing and code reviews focusing on XML processing functions will help prevent similar vulnerabilities from emerging in future versions of the software.