Another bash update. Here's some information included with the patch:
“This patch changes the encoding bash uses for exported functions to avoid
clashes with shell variables and to avoid depending only on an environment
variable's contents to determine whether or not to interpret it as a shell
After this update, an environment variable will not go through the parser
unless it follows this naming structure: BASH_FUNC_*%%
Most scripts never expected to import functions from environment variables,
so this change (although not backwards compatible) is not likely to break
many existing scripts. It will, however, close off access to the parser as
an attack surface in the vast majority of cases. There's already another
vulnerability similar to CVE-2014-6271 for which there is not yet a fix,
but this hardening patch prevents it (and likely many more similar ones).
Thanks to Florian Weimer and Chet Ramey.
(* Security fix *)