CVE-2020-29378
An issue was discovered on V-SOL V1600D V2.03.69 and V2.03.57, V1600D4L V1.01.49, V1600D-MINI V1.01.48, V1600G1 V2.0.7 and V1.9.7, and V1600G2 V1.1.4 OLT devices. It is possible to elevate the privilege of a CLI user (to full administrative access) by using the password !j@l#y$z%x6x7q8c9z) for the enable command.
Source: CVE-2020-29378