Highly unlikely that is a virus or malware. Most likely you account was hacked via other means. They either cracked your password or if you ever used a PC to log into the same account, that was the infected device. My suggestion is to change your social media account passwords from a clean, virus free device and see if the images are still getting leaked.
If you use passwords with things like birthdays, anniversaries or other special significance they make it easier for people to crack. The same goes for the names of family members, pets, ex’s or the type of car you drive or favorite vacation spots.
Too many people use these because they are easy to remember. The problem is if you post anything to social media on those dates or photos tagged with the name it’s even easier to crack your password. You should be using a password of at least 8 to 10 characters and use mixed case, upper and lower and even use a few special characters. Each special char and extra char used in the password makes it exponentially tougher to crack.
You should also never use the same password on multiple sites. If someone does get into an account, say your email, they can go to other sites of yours and ask for a password reset.
It then gets sent to that email address and they can change it and lock you out of your accounts or worse. It’s scary to think, but it happens. It gets worse the more we use different social media accounts and expose personal information.
If you feel you have been hacked, run some anti virus software.Then change all of you password accounts.