Fail2ban findFailure errors lead to disk full

Hi,
I'm fighting a strange problem with Fail2ban.
There is an error happening 1000 times per second and filling log file very fast (1000 lines per second).
After some hours log is 45GB size and disk is full so server goes down.

This is the error :

2016-04-26 19:29:40,999 fail2ban.filter [13939]: ERROR findFailure failed to parse timeText: Apr 25 06:42:50 1008

What cause that ?
How to solve it ?

This is server specs :
Plesk v12.5.30_build1205150826.19 os_Debian 8.0
OS Debian 8.4

I...

Fail2ban findFailure errors lead to disk full