Debian DSA-2305-1 Critical: vsftpd Denial Of Service Threats

Two security issue have been discovered that affect vsftpd, a lightweight,
efficient FTP server written for security.

CVE-2011-2189

It was discovered that Linux kernels < 2.6.35 are considerably slower in
releasing than in the creation of network namespaces. As a result of this
and because vsftpd is using this feature as a security enhancement to
provide network isolation for connections, it is possible to cause denial
of service conditions due to excessive memory allocations by the kernel.
This is technically no vsftpd flaw, but a kernel issue. However, this
feature has legitimate use cases and backporting the specific kernel patch
is too intrusive. Additionally, a local attacker requires the CAP_SYS_ADMIN
capability to abuse this functionality. Therefore, as a fix, a kernel
version check has been added to vsftpd in order to disable this feature
for kernels < 2.6.35.

CVE-2011-0762

Maksymilian Arciemowicz discovered that vsftpd is incorrectly han...