The changelog and notes on the libsndfile overflow reveal that the fix was rushed and details of the severity are not yet decided.

> > could provided a specially-crafted PAF audio file, which once opened by
> > a local, unsuspecting user in an application, linked against libsndfile,
> > could lead to that particular application crash (denial of service),
I agree with everything up to here.

> > or, potentially arbitrary code execution with the privileges of the
> > user running the application.
but this is rubbish. The heap gets overwritten with zeros which would
certainly lead to the application segfaulting. However, there is
no way for arbitrary code to be executed on amy sane OS with proper
memory protection.

Furthermore, Secunia when they contacted me about this said they would
release information about this vulernability on the 18th and then ended
up releasing it on the 12th instead which means I had to rush out the
release I was working on (and would have easily had ready for the
18th). That is not the way to win friends and influence people.