Invalid access to memory

Just clicked through the files on the remote server .. nothing special. Got this error a few times over the last days. Let me know if i can help further ...

WinSCP 5.8.1

Error message:
Invalid access to memory.

Stack trace:
(003C2AD0)
(008300A2)
(0083210A)
(0082F084)
(0008A61F) ntdll.dll
(00077E7A) ntdll.dll.KiUserExceptionDispatcher
(000BB0C8)
(0000249C)
(0082E299)
(00064DE1) ntdll.dll
(00064DA9) ntdll.dll

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.