A incorrect variable in a SUSE specific patch for pam_access rule matching in PAM 1.3.0 in openSUSE Leap 15.0 and SUSE Linux Enterprise 15 could lead to pam_access rules not being applied (fail open).

The _unix_run_helper_binary function in the pam_unix module in Linux-PAM (aka pam) before 1.2.1, when unable to directly access passwords, allows local users to enumerate usernames or cause a denial of service (hang) via a large password.

Multiple directory traversal vulnerabilities in pam_timestamp.c in the pam_timestamp module for Linux-PAM (aka pam) 1.1.8 allow local users to create arbitrary files or possibly bypass authentication via a .. (dot dot) in the (1) PAM_RUSER value to the get_ruser function or (2) PAM_TTY value to the check_tty function, which is used by the format_timestamp_name function.

The _expand_arg function in the pam_env module (modules/pam_env/pam_env.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).

Stack-based buffer overflow in the _assemble_line function in modules/pam_env/pam_env.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 ~/.pam_environment file.

The pam_sm_close_session function in pam_xauth.c in the pam_xauth module in Linux-PAM (aka pam) 1.1.2 and earlier does not properly handle a failure to determine a certain target uid, which might allow local users to delete unintended files by executing a program that relies on the pam_xauth PAM check.

The pam_env module in Linux-PAM (aka pam) 1.1.2 and earlier reads the .pam_environment file in a user's home directory, which might allow local users to run programs with an unintended environment by executing a program that relies on the pam_env PAM check.

The check_acl function in pam_xauth.c in the pam_xauth module in Linux-PAM (aka pam) 1.1.2 and earlier does not verify that a certain ACL file is a regular file, which might allow local users to cause a denial of service (resource consumption) via a special file.

pam_namespace.c in the pam_namespace 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 pam_namespace PAM check, as demonstrated by the sudo program.

The privilege-dropping implementation in the (1) pam_env and (2) pam_mail modules in Linux-PAM (aka pam) 1.1.2 does not check the return value of the setfsuid system call, which might allow local users to obtain sensitive information by leveraging an unintended uid, as demonstrated by a symlink attack on the .pam_environment file in a user's home directory. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-3435.