<<< Date Index >>>     <<< Thread Index >>>

NetBSD kernel local vulnerabilities



Name:          NetBSD kernel local vulnerabilities
Date:          Dec 18, 2004
Author:        Evgeny Demidov

Description:

There exists multiple vulnerabilities in NetBSD binary compatibility code.
They can be approximately divided into two parts:

1) signal number validation problems in xxx_sys_kill(),xxx_sys_sigaction() and 
similar syscalls

These are limited to local DoS only.
By passing large signal numbers to certain syscalls in compat code local 
attacker can crash the kernel.

2) buffer overflows

At least one of them can be exploited to gain full super-user privilegies.

Fix:

NetBSD has issued advisory - 
ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2004-010.txt.asc

History:

Oct 12, 2004 - initial vendor notification
Oct 20, 2004 - NetBSD team performed extensive audit of compat code!
Dec 18, 2004 - public release of this advisory