nss: insecure pkcs11.txt load path (possible code execution)

From the CVE entry:

** DISPUTED ** Untrusted search path vulnerability in Mozilla Network Security Services (NSS), as used in Google Chrome before 17 on Windows and Mac OS X, might allow local users to gain privileges via a Trojan horse pkcs11.txt file in a top-level directory. NOTE: the vendor's response was "Strange behavior, but we're not treating this as a security bug."