A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. When a user drags and drops a directory path of exactly 259 characters without a trailing backslash, the application appends a backslash and null terminator without proper bounds checking, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
https://github.com/notepad-plus-plus/notepad-plus-plus/pull/17930
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/17921