This Tuesday a buffer overflow in the gethostbyname family of functions (“gethostbyname*”) in the widely used glibc library (CVE-2015-0235) was disclosed.  As soon as we became aware of this vulnerability we began investigating.  We regarded it as a significant vulnerabiliy since the original advisory detailed remote code execution in the Exim mail server.

We quickly realized that exploitability of this vulnerability depends on where and how the vulnerable function is invoked.  In particular, if an attacker cannot control the arguments passed to the gethostbyname* functions, then the overflow cannot be triggered.  Suffice it to say, the applicability of this vulnerability to the Exim mail server, cannot be generalized to all software using glibc, or even to all invocations of gethostbyname*.

We have been reviewing the use of glibc and gethostbyname* in our products.  Based on our current analysis, we have not identified any VMware product that is affected by this issue. Many of our products do use a vulnerable version of the glibc library, but we have not found a way to pass untrusted input to gethostbyname*. Our KB on this issue is published here.

We take the security of customers extremely seriously.  Even though no VMware product has been found to be exploitable using this issue, we will update the glibc library in normal upcoming maintenance releases.