CVE-2023-21938: Vulnerability in Oracle Java SE and GraalVM Enterprise Edition Affecting Libraries Component

A new vulnerability has been discovered in Oracle Java SE and Oracle GraalVM Enterprise Edition, CVE-2023-21938, affecting the Libraries component in these products. The vulnerability has a CVSS 3.1 Base Score of 3.7, classified as an integrity impact, which makes it difficult to exploit. Oracle has released security patches for the affected software versions to protect users from unauthorized access to sensitive data.

Exploit Details

This difficult-to-exploit vulnerability allows unauthenticated attackers with network access via multiple protocols to compromise Oracle Java SE and GraalVM Enterprise Edition. Successful attacks may result in unauthorized update, insert, or delete access to some of the accessible data in these products.

The vulnerability specifically applies to Java deployments found in clients running sandboxed Java Web Start applications or sandboxed Java applets. These deployments load and run untrusted code, such as code coming from the internet, and rely on the Java sandbox for security. This vulnerability does not apply to Java deployments that are typically found in servers, which load and run only trusted code (e.g., code installed by an administrator).

To understand the cause of the vulnerability and potential mitigations, a code snippet example is given below.

// Java SE vulnerable Libraries component example

import java.util.*;

public class VulnerableClass {
    public static void main(String[] args) {
        // untrusted code
        String untrustedData = "Some data from the internet";
        // vulnerable operation
        updateData(untrustedData);
    }

    private static void updateData(String data) {
        // performs vulnerable operations on the data
    }
}

In the example above, the updateData() method handles data coming from the internet. An attacker could potentially interfere and manipulate this data, leading to unauthorized access.

Mitigation Steps

Oracle has released security updates to patch the vulnerability for the affected software versions. Users should update their Oracle Java SE and GraalVM Enterprise Edition installations to the latest versions. You can download the updated releases from Oracle's website:

- Oracle Java SE: Download page
- Oracle GraalVM Enterprise Edition: Download page

Additionally, you should ensure that your Java deployment environments only run trusted code and do not rely on sandboxing for security.

For more information on CVE-2023-21938, consult the following resources

- Oracle Critical Patch Update Advisory
- CVE-2023-21938 Details and Mitigations
- Java SE Documentation
- GraalVM Enterprise Edition Documentation

Timeline

Published on: 04/18/2023 20:15:00 UTC
Last modified on: 04/27/2023 15:15:00 UTC