CVE-2019-11500: vulnerability in Dovecot and Pigeonhole

Situation

CVE-2019-11500 vulnerability is found in Dovecot and Pigeonhole.

All Dovecot versions prior to 2.3.7.2 and 2.2.36.4 are affected.

Impact

This vulnerability allows for out-of-bounds writes to objects stored on the heap up to 8096 bytes in pre-login phase, and 65536 bytes post-login phase, allowing a sufficiently skilled attacker to perform complicated attacks that can lead to leaking private information or remote code execution. Abuse of this bug is very difficult to observe, as it does not necessarily cause a crash. Attempts to abuse this bug are not directly evident from logs.

Call to Action

Plesk Team released security patch at the following updates:

• Plesk Obsidian – not affected.

• Plesk 17.8 – available in MU#67

• Plesk 17.5 – available in MU#82

• Plesk 17.0 – available in MU#76

Update your server: How to install Plesk updates

Is the update is not possible for whatever reason switch from Dovecot to Courier:  Log in to Plesk > Tools & Settings > Updates and Upgrades > Add/Remove components: