CVE-2020-13931: 
Java vulnerability analysis and mitigation

CVE-2020-13931 is a security vulnerability affecting Apache TomEE versions 8.0.0-M1 through 8.0.3, 7.1.0 through 7.1.3, 7.0.0-M1 through 7.0.8, and 1.0.0 through 1.7.5. The vulnerability was discovered in 2020 and relates to a misconfiguration issue in the embedded ActiveMQ broker that could expose an unauthenticated JMX port. This vulnerability is particularly notable as it represents an edge case that wasn't fully addressed in the previous fix for CVE-2020-11969 (NVD).

The vulnerability occurs when Apache TomEE is configured to use the embedded ActiveMQ broker with a misconfigured broker configuration. In this scenario, a JMX port is opened on TCP port 1099 without any authentication mechanisms in place. The vulnerability has received a CVSS v3.1 Base Score of 9.8 (CRITICAL) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating its severe nature (NVD).

The exposure of an unauthenticated JMX port can lead to significant security risks, as it provides potential attackers with unauthorized access to the Java Management Extensions interface. This access could potentially allow attackers to execute unauthorized operations, gather sensitive information about the system, and potentially gain control over the application server (NVD).

The vulnerability is considered highly exploitable due to its network accessibility (AV:N) and low attack complexity (AC:L). No special privileges or user interaction are required to exploit this vulnerability, as indicated by the CVSS metrics (NVD).

Users of affected Apache TomEE versions should ensure their ActiveMQ broker configuration is properly secured and upgrade to a patched version of the software. The vulnerability specifically affects configurations using the embedded ActiveMQ broker, so ensuring proper configuration of the broker settings is crucial (NVD).