xterm, including 192-7.el4 in Red Hat Enterprise Linux and 208-3.1 in Debian GNU/Linux, sets the wrong group ownership of tty devices, which allows local users to write data to other users' terminals.
Multiple stack-based buffer overflows in (1) CCE_pinyin.c and (2) xl_pinyin.c in ImmModules/cce/ in unicon-imc2 3.0.4, as used by zhcon and other applications, allow local users to gain privileges via a long HOME environment variable.