LD_PRELOAD

Overview #

• Allows you to load any libraries before loading actual libraries needed by the app
• Can be set via LD_PRELOAD environment variable or on /etc/ld.so.preload

Tools #

• Father

Example exploits leveraging this technique #

• GNU Screen 4.5.0 - Local Privilege Escalation

References #

• https://securityboulevard.com/2020/10/not-so-random-using-ld_preload-to-hijack-the-rand-function/
• Linux Privilege Escalation using LD_Preload