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

sppp -- buffer overflow vulnerability

Affected systems
FreeBSD < 4.11_20
5.3 <= FreeBSD < 5.3_32
5.4 <= FreeBSD < 5.4_17
5.5 <= FreeBSD < 5.5_3
6.0 <= FreeBSD < 6.0_10
6.1 <= FreeBSD < 6.1_4


VuXML ID c9d2e361-32fb-11db-a6e2-000e0c2e438a
Discovery 2006-08-23
Entry 2006-08-23
Modified 2006-08-30

Problem Description

While processing Link Control Protocol (LCP) configuration options received from the remote host, sppp(4) fails to correctly validate option lengths. This may result in data being read or written beyond the allocated kernel memory buffer.


An attacker able to send LCP packets, including the remote end of a sppp(4) connection, can cause the FreeBSD kernel to panic. Such an attacker may also be able to obtain sensitive information or gain elevated privileges.


No workaround is available, but systems which do not use sppp(4) are not vulnerable.


CVE Name CVE-2006-4304
FreeBSD Advisory SA-06:18.ppp