CVE-2017-14469

Name of the Vulnerable Software and Affected Versions: Allen Bradley Micrologix 1400 Series B versions 21.2 and before

Description: The issue allows for an exploitable access control vulnerability in the data, program, and function file permissions functionality. A specially crafted packet can cause a read or write operation, resulting in disclosure of sensitive information, modification of settings, or modification of ladder logic. An attacker can send unauthenticated packets to trigger this issue. The vulnerability is associated with a non-user fault type and fault code 0028, which can be triggered by setting invalid values (0x01 and 0x02) for the user fault routine. This can be done by writing directly to the file, and when the device is moved into a run state, a fault is triggered.

Recommendations: For Allen Bradley Micrologix 1400 Series B versions 21.2 and before, consider restricting access to the device to prevent unauthenticated packets from being sent, and avoid writing directly to the file to set invalid values for the user fault routine. As a temporary workaround, consider disabling remote access when not necessary to minimize the risk of exploitation.