pamnamespace.c in the pamnamespace module in Linux-PAM (aka pam) before 1.1.3 uses the environment of the invoking application or service during execution of the namespace.init script, which might allow local users to gain privileges by running a setuid program that relies on the pamnamespace PAM check, as demonstrated by the sudo program.
Stack-based buffer overflow in the assembleline function in modules/pamenv/pamenv.c in Linux-PAM (aka pam) before 1.1.5 allows local users to cause a denial of service (crash) and possibly execute arbitrary code via a long string of white spaces at the beginning of the ~/.pamenvironment file.
The expandarg function in the pamenv module (modules/pamenv/pamenv.c) in Linux-PAM (aka pam) before 1.1.5 does not properly handle when environment variable expansion can overflow, which allows local users to cause a denial of service (CPU consumption).