Apache Struts External Entity (XXE) Injection Vulnerability S2-069 (CVE-2025-68493)

Overview

Recently, NSFOCUS CERT detected that Apache issued a security bulletin to fix the Apache Struts external entity (XXE) injection vulnerability S2-069 (CVE-2025-68493); Because the XWork component of Apache Struts does not perform effective validation when parsing XML configuration, attackers can inject external entities by constructing malicious XML data to read sensitive server files, perform server-side request forgery or denial of service attacks. CVSS score 9.8, affected users should take protective measures as soon as possible.

Reference link: https://cwiki.apache.org/confluence/display/WW/S2-069

Scope of Impact

Affected versions

• 2.0.0 <= Apache Struts <= 2.3.37(EOL)
• 2.5.0 <= Apache Struts <= 2.5.33(EOL)
• 6.0.0 <= Apache Struts <= 6.1.0

Unaffected version

• Apache Struts >= 6.1.1

Detection

Manual check

For projects packaged with maven, users can view the current version of struts used through pom.xml:

Users can also view the struts version by viewing the core package in lib:

If the current version is within the affected range, there may be a security risk.

Risk Investigation of Exposure Surface

Cloud detection

NSFOCUS External Attack Surface Management Service (EASM) supports the Internet asset investigation of CVE-2025-68493 vulnerability risks. It has helped service customer groups complete exposure surface investigations and conduct vulnerability warnings and closed-loop disposal in a timely manner before threats occur. Interested customers can arrange detailed consultation and communication by contacting their local regional colleagues at NSFOCUS or sending an email to rs@nsfocus.com.

Tool troubleshooting

NSFOCUS Automated Penetration Testing Tool (EZ) supports Apache Struts service identification and can be scanned directly using web modules. (Note: For the enterprise version, please contact NSFOCUS sales team)

Mitigation

Official upgrade

At present, the official has released a new version to fix this vulnerability. Affected users are requested to upgrade the version as soon as possible for protection.

Download link: https://struts.apache.org/download.cgi

Temporary protective measures

If the relevant users are temporarily unable to perform upgrade operations, temporary relief can be achieved through the following measures:

1. Use the custom SAXParserFactory configuration and set the system xwork.saxParserFactory= to point to the custom factory class to disable external entities by default;

2. Configure the following system properties in the JVM startup parameters to disable external entity access to the default XML parser;

Note: Setting it to an empty string blocks all protocols.

Statement

This advisory is only used to describe a potential risk. NSFOCUS does not provide any commitment or promise on this advisory. NSFOCUS and the author will not bear any liability for any direct and/or indirect consequences and losses caused by transmitting and/or using this advisory. NSFOCUS reserves all the rights to modify and interpret this advisory. Please include this statement paragraph when reproducing or transferring this advisory. Do not modify this advisory, add/delete any information to/from it, or use this advisory for commercial purposes without permission from NSFOCUS.

About NSFOCUS

NSFOCUS, a pioneering leader in cybersecurity, is dedicated to safeguarding telecommunications, Internet service providers, hosting providers, and enterprises from sophisticated cyberattacks.

Founded in 2000, NSFOCUS operates globally with over 4000 employees at two headquarters in Beijing, China, and Santa Clara, CA, USA, and over 50 offices worldwide. It has a proven track record of protecting over 25% of the Fortune Global 500 companies, including four of the five largest banks and six of the world’s top ten telecommunications companies.

Leveraging technical prowess and innovation, NSFOCUS delivers a comprehensive suite of security solutions, including the Intelligent Security Operations Platform (ISOP) for modern SOC, DDoS Protection, Continuous Threat Exposure Management (CTEM) Service and Web Application and API Protection (WAAP). All the solutions and services are augmented by the Security Large Language Model (SecLLM), ML, patented algorithms and other cutting-edge research achievements developed by NSFOCUS.