Title: FreeBSD IP Fragment Queue Resource Exhaustion Vulnerability
Severity: HIGH
Description:
FreeBSD contains a vulnerability in it's TCP/IP implementation that may lead to possible denial of service conditions.
When the kernel receives IP fragments, a reassembly queue is created. This queue stores all recieved IP fragments for a specific IP ID for 30 seconds. On vulnerable FreeBSD systems, there is no limit on how many queues can be created. This opens up a possibility for attack.
A remote attacker may be able to exhaust resources by causing the creation of a large number of reassembly queues. This would be accomplished by quickly sending a large number of IP fragments with different IP IDs to the target host. As more queues are created, resources will be consumed and eventually none will remain for legitimate network traffic.
With mbufs depleted, an affected host will not be able to send or recieve traffic until the attack finishes and the queues are cleared.
NetBSD, OpenBSD and BSDI may also be vulnerable to this attack.
Affected Products:
- FreeBSD FreeBSD 3.0.0
- FreeBSD FreeBSD 3.1.0
- FreeBSD FreeBSD 3.2.0
- FreeBSD FreeBSD 3.3.0
- FreeBSD FreeBSD 3.4.0
- FreeBSD FreeBSD 3.5.0
- FreeBSD FreeBSD 3.5.1
- FreeBSD FreeBSD 4.0.0
- FreeBSD FreeBSD 4.1.0
- FreeBSD FreeBSD 4.1.1
- FreeBSD FreeBSD 4.2.0
- FreeBSD FreeBSD 4.3.0
Juniper Networks provides this content via a wide variety of sources and production methods. If notified of errors or omissions in the content of this page, Juniper Networks, at its discretion, will modify or remove the page or leave the content as is, depending on various factors including but not limited to the reputation and authority of the party providing the notification. Please use the contact information displayed elsewhere on this page to report any errors or omissions regarding the content on this page.
