Many friends keep complaining about updates on their timeline that they did not post. Unknowingly to these people, they granted permission to an application that is posting on their behalf. The permission was granted while they click on such link and they were asked to provide their login details before they could check what they are looking for. The curiosity to check that nude babe won't allow many to see that you to see that the app is requesting permission to post on your behalf, you there by start the posting of such updates on your timeline. In short stop attending to links with explicit content or you start distributing the content.

DO U WANT TO STOP THAT EXPLICIT UPDATE ON YOUR TIMELINE?
Take the following steps.
1. Check for the name of the app that is doing the auto update.
2. Go to your Facebook settings.
3. Look for app settings.
4. Check for the application posting on your timeline.
5. Remove the application from the list of app that you use on Facebook as well as it's contents.

Doing all these will set you free.

changing ur password also helps

Sunkyphil:
changing ur password also helps

though changing password is good when such happen but it won't stop the update from application that have your permission already.

change your password and change your settings to notify you whenever you want to login from any mobile device/PC to send you a notification and code that would be sent as SMS.