OpenBSD Pending ARP Request Remote DoS Vulnerability
BID:1759
Info
OpenBSD Pending ARP Request Remote DoS Vulnerability
| Bugtraq ID: | 1759 |
| Class: | Failure to Handle Exceptional Conditions |
| CVE: | |
| Remote: | Yes |
| Local: | Yes |
| Published: | Oct 05 2000 12:00AM |
| Updated: | Oct 05 2000 12:00AM |
| Credit: | This vulnerability was reported to bugtraq by skyper <[email protected]> on 5 Oct 2000. |
| Vulnerable: |
OpenBSD OpenBSD 2.6 OpenBSD OpenBSD 2.5 OpenBSD OpenBSD 2.4 OpenBSD OpenBSD 2.3 OpenBSD OpenBSD 2.2 OpenBSD OpenBSD 2.1 OpenBSD OpenBSD 2.0 |
| Not Vulnerable: |
OpenBSD OpenBSD 2.7 |
Discussion
OpenBSD Pending ARP Request Remote DoS Vulnerability
OpenBSD is vulnerable to a remotely exploitable denial of service condition. The problem seems to be a lack of limits on the storage of pending arp requests, and a failure to handle the condition of too many. If an attacker somehow causes a victim machine to send out too many arp requests, it can cause a kernel panic and the target system to halt.
If an OpenBSD machine is on a network with a large address space (much more than a class C) an attacker can send it spoofed packets with addresses of hosts within its network. The victim host would then send out arp requests to find the MAC address for each host. If a sufficient number of arp requests are sent out, the kernel will panic with the message:
"out of space in kmem_map"
and freeze.
OpenBSD is vulnerable to a remotely exploitable denial of service condition. The problem seems to be a lack of limits on the storage of pending arp requests, and a failure to handle the condition of too many. If an attacker somehow causes a victim machine to send out too many arp requests, it can cause a kernel panic and the target system to halt.
If an OpenBSD machine is on a network with a large address space (much more than a class C) an attacker can send it spoofed packets with addresses of hosts within its network. The victim host would then send out arp requests to find the MAC address for each host. If a sufficient number of arp requests are sent out, the kernel will panic with the message:
"out of space in kmem_map"
and freeze.
Exploit / POC
OpenBSD Pending ARP Request Remote DoS Vulnerability
An exploit has been made available.
An exploit has been made available.
Solution / Fix
OpenBSD Pending ARP Request Remote DoS Vulnerability
Solution:
This vulnerability has been fixed in OpenBSD 2.7.
Solution:
This vulnerability has been fixed in OpenBSD 2.7.
References
OpenBSD Pending ARP Request Remote DoS Vulnerability
References:
References: