heap-buffer-overflow exists in the function handleEditText in swfdump.c

[cxlzff]

system info

Ubuntu x86_64, clang 6.0, swfdump (latest master a9d5082)

Command line

./src/swfdump -D @@

AddressSanitizer output

==44192==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60600000e8d3 at pc 0x000000410aca bp 0x7fffffffdee0 sp 0x7fffffffded0 READ of size 1 at 0x60600000e8d3 thread T0 #0 0x410ac9 in handleEditText /test/swftools-asan/src/swfdump.c:549 #1 0x408624 in main /test/swftools-asan/src/swfdump.c:1511 #2 0x7ffff68a683f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f) #3 0x40c168 in _start (/test/swftools-asan/src/swfdump+0x40c168)

0x60600000e8d3 is located 0 bytes to the right of 51-byte region [0x60600000e8a0,0x60600000e8d3) allocated by thread T0 here: #0 0x7ffff6f02602 in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x98602) #1 0x532fa7 in rfx_alloc /test/swftools-asan/lib/mem.c:30 #2 0x541396 (/test/swftools-asan/src/swfdump+0x541396)

SUMMARY: AddressSanitizer: heap-buffer-overflow /test/swftools-asan/src/swfdump.c:549 handleEditText Shadow bytes around the buggy address: 0x0c0c7fff9cc0: 00 00 00 00 00 00 02 fa fa fa fa fa 00 00 00 00 0x0c0c7fff9cd0: 00 00 00 fa fa fa fa fa 00 00 00 00 00 00 00 fa 0x0c0c7fff9ce0: fa fa fa fa 00 00 00 00 00 00 00 05 fa fa fa fa 0x0c0c7fff9cf0: 00 00 00 00 00 00 00 fa fa fa fa fa 00 00 00 00 0x0c0c7fff9d00: 00 00 00 fa fa fa fa fa 00 00 00 00 00 00 00 fa =>0x0c0c7fff9d10: fa fa fa fa 00 00 00 00 00 00[03]fa fa fa fa fa 0x0c0c7fff9d20: 00 00 00 00 00 00 00 fa fa fa fa fa 00 00 00 00 0x0c0c7fff9d30: 00 00 00 fa fa fa fa fa 00 00 00 00 00 00 00 fa 0x0c0c7fff9d40: fa fa fa fa 00 00 00 00 00 00 00 fa fa fa fa fa 0x0c0c7fff9d50: 00 00 00 00 00 00 00 fa fa fa fa fa 00 00 00 00 0x0c0c7fff9d60: 00 00 00 fa fa fa fa fa 00 00 00 00 00 00 00 fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe ==44192==ABORTING

POC handleEditText_poc