Red Hat GDB: out-of-bounds write

A flaw was found in GDB's STABS debug format parser. The

read_member_functions() function in gdb/stabsread.c contains a linked

list removal bug in the code that separates destructor and non-destructor

member functions of C++ classes. The bug causes the destructor entries to

remain in the main function list while the list length counter is

decremented, resulting in an out-of-bounds write when the function list

is copied to its final allocated array. An attacker can craft an ELF

binary with malicious .stab and .stabstr sections that triggers this

out-of-bounds write when a user opens the file in GDB and performs any

symbol-inspection operation such as setting a breakpoint. The inferior

process does not need to be executed. Under controlled conditions, this

was demonstrated to achieve execution of arbitrary commands within the

GDB process.