Vulnerability : denial of service Problem type : remote Debian-specific: no Debian bug : 622741 629373 CVE IDs : CVE-2011-0762 CVE-2011-2189
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 handling
certain glob expressions in STAT commands. This allows a remote authenticated
attacker to conduct denial of service attacks (excessive CPU and process
slot exhaustion) via crafted STAT commands.
2.0.7-1+lenny12.3.2-3+squeeze2