In mid-October, a 9-year-old serious flaw on the kernel of Linux operating system was discovered. Named Dirty COW, the flaw affects all Linux system from version 2.6.22. According to Bkav, Vietnam now has 5,058 affected systems including important services such as FTP Server and Webserver.
Dirty COW is cataloged a privilege escalation vulnerabilitiy. Exploiting successfully Dirty COW, a hacker with an user account (limited right) can escalate to admin on the system. There are two reasons that make the vulnerability the most serious privilege escalation ever. First, it's not hard to develop exploits that work reliably. For another, the flaw is located in a section of the Linux kernel that's a part of virtually every distribution of the open-source OS released for almost a decade. Bkav has recorded many sources publishing COW Dirty exploit.
Mr. Bui Tien Dung – Bkav System Security expert said: "In the actual attacks, Dirty COW can be combined with several common errors such as SQL injection, Buffer Overflow... to take full control of the victim system with the highest authority (root, system ...)".
Bkav provides testing tool combined patch update at link: https://www.tools.whitehat.vn/dirtyCow.zip
Users and system administrators should download the tool and run the command [python DirtyCOW] to fix the problem as soon as possible. The tool will automatically check whether the system has vulnerabilities or not and patch it (system required Python installation).