Application crash via pseudo-zero range reduction

Stack-based buffer overflow in GNU C Library before 2.32 allows local users to crash applications via malformed 80-bit long doubles. The __ieee754_rem_pio2l range reducer passes pseudo-zero or unnormal representations to __kernel_rem_pio2 even though that routine requires normalized input, causing an unsafe all-zero working array to corrupt the stack. Exploitation requires attacker-controlled binary data to reach an x86 long-double trigonometric call; observed overwrites are constrained to zero values and are likely to crash the calling process.