Warning! Spoilers ahead for Superman #32 and Infinite Frontier: Secret Files #4!
One of Superman's greatest weaknesses is his vulnerability to telepathic attacks, but it turns out DC's oldest villain, Vandal Savage, is immune to them. Despite being one of DC's strongest characters, like all people, Superman has weaknesses. His most well-known weakness is his vulnerability to Kryptonite. Alongside this, being under a red sun greatly dampens his powers. Naturally, Superman's greatest villains have taken advantage of these methods to get the upper hand on the Man of Steel.
Although usually a villain, Vandal Savage of Earth-23 is part of DC's newest multiversal team, the Totality, as showcased in Infinite Frontier: Secret Files #4 by Brandon Thomas, Joshua Williamson, Inaki Miranda, and Nick Filardi. Vandal is an immortal warrior who has lived for thousands of years, making him one of DC's oldest villains. Having lived through eons, he has garnered immunity to a lot of potential threats over the centuries. Vandal doesn't possess the power set that Superman has, but there's one thing that he's invulnerable to that makes him stronger than Superman in some ways.
Due to his immense power, the worst thing that could happen to Superman would be his being taken control of by someone else. Superman's strengths in the wrong hands could prove devastating to the world and the hero's vulnerability to telepathy has become more and more evident as of recent. However, Infinite Frontier: Secret Files #4 reveals that Martian Manhunter can't mind control Vandal Savage, as he is immune to it while Superman is vulnerable. The issue also suggests Martian Manhunter might face off against Superman soon. If they were to fight, Superman would most likely be overtaken by J'onn's telepathic abilities. Although Superman has lived through a lot and is incredibly powerful, he simply hasn't had the amount of time to adapt as Vandal Savage has.
However, it isn't just telepathy that is one of Superman's greatest weaknesses. It's his ability to be controlled by other beings, as seen in Superman #32. In this issue, Superman is taken over by the Shadowbreed. If they were successfully able to use Superman's body as a conduit, they could've done some serious damage to whoever their next target would have been. However, Superman manages to break free of their control, bursting out. He states that he thinks the Shadowbreed aren't used to controlling hosts as strong as Kryptonians. Therefore, it's clear that his extreme powers can get him out of some villains' sway, in rare cases.
Ultimately, Superman lacks Vandal Savage's power of telepathic immunity, which makes him susceptible to people taking control over him. This immunity would be hugely beneficial to the Man of Steel as it would limit his weakness to just Kryptonite and red suns. But for now, DC is sticking to the idea of Superman being vulnerable to telepathy.