pyxtrlock before 0.1 uses an incorrect variable name, which allows physically proximate attackers to bypass the lock screen via multiple failed authentication attempts, which trigger a crash.

pyxtrlock before 0.2 does not properly check the return values of the (1) xcb_grab_pointer and (2) xcb_grab_keyboard XCB library functions, which allows physically proximate attackers to gain access to the keyboard or mouse without unlocking the screen via unspecified vectors.