Openbsd » Openbsd : Security Vulnerabilities, CVEs, Published In 2006 CVSS score >= 6

OpenBSD and NetBSD permit usermode code to kill the display server and write to the X.Org /dev/xf86 device, which allows local users with root privileges to reduce securelevel by replacing the System Management Mode (SMM) handler via a write to an SMRAM address within /dev/xf86 (aka the video card memory-mapped I/O range), and then launching the new handler via a System Management Interrupt (SMI), as demonstrated by a write to Programmed I/O port 0xB2.

The _dl_unsetenv function in loader.c in the ELF ld.so in OpenBSD 3.9 and 4.0 does not properly remove duplicate environment variables, which allows local users to pass dangerous variables such as LD_PRELOAD to loading processes, which might be leveraged to gain privileges.

Buffer overflow in the sppp driver in FreeBSD 4.11 through 6.1, NetBSD 2.0 through 4.0 beta before 20060823, and OpenBSD 3.8 and 3.9 before 20060902 allows remote attackers to cause a denial of service (panic), obtain sensitive information, and possibly execute arbitrary code via crafted Link Control Protocol (LCP) packets with an option length that exceeds the overall length, which triggers the overflow in (1) pppoe and (2) ippp. NOTE: this issue was originally incorrectly reported for the ppp driver.