runtime/staprun/staprun_funcs.c in the systemtap runtime tool (staprun) in SystemTap before 1.6 does not properly validate modules when a module path is specified by a user for user-space probing, which allows local users in the stapusr group to gain privileges via a crafted module in the search path in the -u argument.
The insert_module function in runtime/staprun/staprun_funcs.c in the systemtap runtime tool (staprun) in SystemTap before 1.6 does not properly validate a module when loading it, which allows local users to gain privileges via a race condition between the signature validation and the module initialization.
SystemTap 1.4 and earlier, when unprivileged (aka stapusr) mode is enabled, allows local users to cause a denial of service (divide-by-zero error and OOPS) via a crafted ELF program with DWARF expressions that are not properly handled by a stap script that performs context variable access.
The staprun runtime tool in SystemTap 1.3 does not properly clear the environment before executing modprobe, which allows local users to gain privileges by setting the MODPROBE_OPTIONS environment variable to specify a malicious configuration file.
The staprun runtime tool in SystemTap 1.3 does not verify that a module to unload was previously loaded by SystemTap, which allows local users to cause a denial of service (unloading of arbitrary kernel modules).