Solving a CTF challenge: Exploiting a Buffer Overflow (video)

Capture The Flag (CTF) competitions are an entertaining way to practice and/or improve your skills. NVISO staff regularly participates in CTF competitions, in particular when the competition focuses on IT security. We produced a video with step-by-step analysis of a CTF executable containing a buffer overflow. This executable is running on a server, and by … Continue reading Solving a CTF challenge: Exploiting a Buffer Overflow (video)

The GHOST vulnerability

A serious problem in the Linux glibc library went unnoticed for almost 15 years. A simple coding mistake introduced into the code in November 2000 leaves servers including e-mail servers vulnerable to remote code execution. A buffer overflow in the GNU C Library function __nss_hostname_digits_dots(), which is called by the well used gethostbyname*() functions makes … Continue reading The GHOST vulnerability