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.