The problem is fixed. Valve suggests to change the password and to reset Steam Guard.
Valve is currently working on a solution to fix the issue.
Some more details on the Heartbleed bug: http://heartbleed.com/
The App-IDs were added about a year ago and then deleted over eleven months ago. http://www.steamgamer.de/ne...
The problem is fixed. Valve suggests to change the password and to reset Steam Guard.