FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

FreeBSD -- TCP reassembly vulnerability

Affected packages
8.4 <= FreeBSD-kernel < 8.4_9
8.3 <= FreeBSD-kernel < 8.3_16
9.2 <= FreeBSD-kernel < 9.2_5
9.1 <= FreeBSD-kernel < 9.1_12
10.0 <= FreeBSD-kernel < 10.0_2


VuXML ID 6d472244-6007-11e6-a6c3-14dae9d210b8
Discovery 2014-04-30
Entry 2016-08-11

Problem Description:

FreeBSD may add a reassemble queue entry on the stack into the segment list when the reassembly queue reaches its limit. The memory from the stack is undefined after the function returns. Subsequent iterations of the reassembly function will attempt to access this entry.


An attacker who can send a series of specifically crafted packets with a connection could cause a denial of service situation by causing the kernel to crash.

Additionally, because the undefined on stack memory may be overwritten by other kernel threads, while extremely difficult, it may be possible for an attacker to construct a carefully crafted attack to obtain portion of kernel memory via a connected socket. This may result in the disclosure of sensitive information such as login credentials, etc. before or even without crashing the system.


CVE Name CVE-2014-3000
FreeBSD Advisory SA-14:08.tcp