For many users, converting Office documents into PDF files is part of everyday life. There are many free applications to be found online to help with this task. Yet many tools contain malware or are installing a permanent backdoor to your system.
A severe vulnerability has been found in two widely used free PDF editors. As reported by the G-DATA security company, the “AppSuite PDF Editor” and “OneStart PDF Editor” apps contain a hidden backdoor which enables attackers to take full control of an affected system.
This malware is designed in a way which allows attackers to run any commands or software, opening up a variety of options for abuse – from downloading further malware to capturing confidential information. One particular perfidious aspect is the mechanism these apps are using to try and protect themselves against discovery: They were transmitted to security companies in the hope of them adding these apps to their “permitted” lists, intended to prevent antivirus software from blocking infected files.
The biggest problem for users is that the backdoor installed is not necessarily removed if they de-install the software. As a final consequence, a complete new installation of their operating system is required to reliably clean their system.
It is strongly advisable not to rely on any free PDF editors. Instead, you should obtain software only from well-known and trustworthy sources. Please also read our article on “How to download programs and apps safely” which deals with this topic. In addition, regular updates and using current security software will also provide protection.
