"The FBI has warned users of Asterisk to upgrade to the
most current version, although it has not specified which version
has the bug.
"Asterisk is one of the more mature open source VoIP platforms,
and its parent company Digium has continued to develop commercial
success even as it has improved its open source offering, as we
wrote about here. Quite a few businesses use older versions of
Asterisk, though, and that's the problem according to this advisory
from the FBI:"