Big Fish: Exploiting a 37-Year-Old Kernel Bug in OpenBSD

The Big Fish vulnerability, discovered by researchers at CALIF, is a 37-year-old kernel bug in OpenBSD that can be exploited to gain root privileges. The bug, which affects OpenBSD versions 4.5 to 7.5, is due to a flaw in the `inet.c` file that allows an attacker to cause a buffer overflow and execute arbitrary code. The vulnerability was discovered by examining an old version of the OpenBSD kernel and has been confirmed to be exploitable on systems running OpenBSD 4.5 to 7.5. To exploit the bug, an attacker must have the ability to run code on the system and have a way to trigger the buffer overflow.