CVE-2023-25926 - XML External Entity Injection (XXE) vulnerability in IBM Security Guardium Key Lifecycle Manager and its implications

IBM Security Guardium Key Lifecycle Manager (GKLM) is widely utilized to manage encryption keys across an organization, ensuring protection against unauthorized data loss. It plays a critical role in securing information, and as such, system vulnerabilities present a major cause for concern. In this article, we will delve into CVE-2023-25926, an XML External Entity Injection (XXE) vulnerability in GKLM versions 3., 3..1, 4., 4.1, and 4.1.1. This vulnerability allows remote attackers to expose sensitive information or consume memory resources. We will provide details on the exploit, code snippets, and relevant references to help you understand and safeguard your systems from this attack. IBM X-Force ID associated with this vulnerability is 247599.

Vulnerability Details

An XXE attack is a type of security vulnerability that allows attackers to exploit an XML parser by injecting malicious XML code into the targeted application. The CVE-2023-25926 vulnerability allows an attacker to exploit GKLM when it processes XML data. As a result, sensitive information can be accessed, and memory resources can be overwhelmed, causing a potential denial of service (DoS) attack.

Exploit Details

To exploit the XXE vulnerability in GKLM, an attacker is required to send a malicious XML file to the vulnerable application. The XML file must contain carefully crafted external entities that exploit the XML parser to access sensitive data or consume excessive memory resources.

A typical XXE attack using a malicious XML file may look like this

<?xml version="1." encoding="UTF-8"?>
<!DOCTYPE foo [
<!ELEMENT foo ANY >
<!ENTITY xxe SYSTEM "file:///etc/passwd" >]>
<foo>&xxe;</foo>

In this example, the XML file has an external entity called "xxe" referencing a locally stored sensitive file (/etc/passwd) that contains user account information. The XML parser processes the entity reference, exposing the sensitive data by echoing its content.

Action and Mitigation

IBM has acknowledged the vulnerability and recommends upgrading IBM Security Guardium Key Lifecycle Manager to version 4.1.2 or higher, where the issue has been resolved. Also, administrators should disable the processing of external XML entities within the XML parser to minimize the risk of this vulnerability. Patches and updates can be obtained from IBM Fix Central:

https://www.ibm.com/support/fixcentral/

To disable external entities processing, ensure that the following configuration is set within the Java-based XML parser:

import javax.xml.XMLConstants;

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);

Conclusion

CVE-2023-25926, an XML External Entity Injection (XXE) vulnerability in IBM Security Guardium Key Lifecycle Manager, is a serious security issue that can expose sensitive information and consume memory resources. Proper understanding, timely updates, and adherence to best practices are crucial in safeguarding your systems against this and other vulnerabilities. Keep your systems updated, and stay informed to maintain a secure environment.

References

1. IBM Security Bulletin: https://www.ibm.com/support/pages/node/6472427
2. CVE-2023-25926 Details: https://nvd.nist.gov/vuln/detail/CVE-2023-25926
3. IBM X-Force Vulnerability Report: https://exchange.xforce.ibmcloud.com/vulnerabilities/247599
4. IBM Fix Central: https://www.ibm.com/support/fixcentral/

Timeline

Published on: 02/29/2024 01:38:24 UTC
Last modified on: 02/29/2024 13:49:47 UTC