Generally safe area between Tufts and Davis Square. Much of the area around Tufts is residential with nice houses. Davis Square is pretty active into the evening.
But, as @MAnerdmom, wrote that bad things can still happen and as @blossom noted, situational awareness is key. The probability of bad things happening is probably quite a bit higher if the person is not situationally aware and also if the person walking around is female rather than male.