<Try to describe precise steps that lead to the problem (where do you click, what keys do you press, what do you see, etc.)>
<If relevant, consider attaching a session log file or a screenshot)>

WinSCP 5.11.2

Error message:
Invalid access to memory.

Stack trace:
(003C8D45)
(003C8D45)
(00257C85)
(0021214C)

(00075664)
(000624F6) ntdll.dll
(0000F13E) ntdll.dll.KiUserExceptionDispatcher
(007E7D5F)
(00257C85)
(001BFE14)
(00257DEB)
(00257C85)
(0021214C)

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.