Dear all, as it turns out, the latest security update to grep changed the behavior of a recursive search through stdin. Previously the command echo test | grep -r test (which is undoubtedly a bit buggy in itself) would ignore the -r and search through the input. With grep 2.20, this command will recursively traverse all files starting from the current directory. This problem occurred in one of the CernVM scripts but I assume we won't be the only ones hitting it. If you have the possibility to provide feedback to Red Hat, we would very much appreciate if the old behavior was restored. As a more general feedback, at least for CernVM, we think a strict separation between security updates and feature updates would be very helpful. Cheers, Jakob