glibc: printf() unbound alloca() usage in case of positional parameters + many format specs

The vfprintf function in stdio-common/vfprintf.c in GNU C Library aka glibc 2.5, 2.12, and probably other versions does not "properly restrict the use of" the alloca function when allocating the SPECS array, which allows context-dependent attackers to bypass the FORTIFYSOURCE format-string...

glibc: printf() unbound alloca() usage in case of positional parameters + many format specs

The vfprintf function in stdio-common/vfprintf.c in GNU C Library aka glibc 2.5, 2.12, and probably other versions does not "properly restrict the use of" the alloca function when allocating the SPECS array, which allows context-dependent attackers to bypass the FORTIFYSOURCE format-string...