Project: libredwg (libredwg/libredwg), language: c++
Vulnerability instance: libredwg.cve-2019-20014
Sanitizer: address

================= Bug Report (1/2) ==================
## Source: GitHub Issue
## URL: https://github.com/LibreDWG/libredwg/issues/176
## Description:
Issue: LibreDWG/libredwg#176
Title: Several bugs found by fuzzing
State: closed
Created by: linhlhq
Created at: 2019-12-24 03:44:32+00:00
Labels: bug, fuzzing

Issue Body:
Hi,
After fuzzing libredwg, I found the following bugs on the latest commit on master.
Command: dwg2dxf $PoC
**1.Crafted input will lead to Memory allocation failed in dwg_decode_SPLINE_private (src/dwg.spec:1639)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000000%2Csig:06%2Csrc:000000%2Cop:flip1%2Cpos:36317
ASAN says:
```
==6231==ERROR: AddressSanitizer failed to allocate 0xd54f86000 (57260138496) bytes of LargeMmapAllocator (error code: 12)
==6231==Process memory map follows:
	0x00007fff7000-0x00008fff7000
	0x00008fff7000-0x02008fff7000
	0x02008fff7000-0x10007fff8000
	0x55f7ba14f000-0x55f7bb643000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x55f7bb843000-0x55f7bb85b000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x55f7bb85b000-0x55f7bb93f000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x55f7bb93f000-0x55f7bb943000
	.....
	0x7fd78077d000-0x7fd780794000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fd780794000-0x7fd780993000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fd780993000-0x7fd780994000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fd780994000-0x7fd780995000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fd780995000-0x7fd7809af000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fd7809af000-0x7fd780bae000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fd780bae000-0x7fd780baf000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fd780baf000-0x7fd780bb0000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fd780bb0000-0x7fd780bb4000
	0x7fd780bb4000-0x7fd780bbb000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fd780bbb000-0x7fd780dba000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fd780dba000-0x7fd780dbb000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fd780dbb000-0x7fd780dbc000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fd780dbc000-0x7fd780dbf000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fd780dbf000-0x7fd780fbe000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fd780fbe000-0x7fd780fbf000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fd780fbf000-0x7fd780fc0000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fd780fc0000-0x7fd7811a7000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fd7811a7000-0x7fd7813a7000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fd7813a7000-0x7fd7813ab000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fd7813ab000-0x7fd7813ad000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fd7813ad000-0x7fd7813b1000
	0x7fd7813b1000-0x7fd78154e000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fd78154e000-0x7fd78174d000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fd78174d000-0x7fd78174e000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fd78174e000-0x7fd78174f000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fd78174f000-0x7fd78189f000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fd78189f000-0x7fd781a9f000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fd781a9f000-0x7fd781aa2000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fd781aa2000-0x7fd781aa5000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fd781aa5000-0x7fd78270a000
	0x7fd78270a000-0x7fd782731000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fd78279d000-0x7fd782927000
	0x7fd782927000-0x7fd782931000
	0x7fd782931000-0x7fd782932000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fd782932000-0x7fd782933000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fd782933000-0x7fd782934000
	0x7fffa34fe000-0x7fffa351f000	[stack]
	0x7fffa35bc000-0x7fffa35bf000	[vvar]
	0x7fffa35bf000-0x7fffa35c1000	[vdso]
	0xffffffffff600000-0xffffffffff601000	[vsyscall]
==6231==End of process memory map.
==6231==AddressSanitizer CHECK failed: ../../../../src/libsanitizer/sanitizer_common/sanitizer_common.cc:118 "((0 && "unable to mmap")) != (0)" (0x0, 0x0)
    #0 0x7fd781838c02  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xe9c02)
    #1 0x7fd781857595 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x108595)
    #2 0x7fd781842492  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xf3492)
    #3 0x7fd78184e8a5  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xff8a5)
    #4 0x7fd78177b8f1  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2c8f1)
    #5 0x7fd78177604b  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2704b)
    #6 0x7fd78182dd00 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded00)
    #7 0x55f7ba79bec8 in dwg_decode_SPLINE_private ../../src/dwg.spec:1639
    #8 0x55f7ba7a4e19 in dwg_decode_SPLINE ../../src/dwg.spec:1585
    #9 0x55f7bab4b89b in dwg_decode_add_object ../../src/decode.c:4738
    #10 0x55f7bab5ef28 in decode_R13_R2000 ../../src/decode.c:1216
    #11 0x55f7bab9161a in dwg_decode ../../src/decode.c:239
    #12 0x55f7ba533f7a in dwg_read_file ../../src/dwg.c:206
    #13 0x55f7ba53232d in main ../../programs/dwg2dxf.c:255
    #14 0x7fd780fe1b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #15 0x55f7ba5332e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)
```
Thanks,
Linhlhq from Infiniti Team, VinCSS (a member of Vingroup) # #


Comments:
Comment by linhlhq on 2019-12-24 03:45:01+00:00:
**2.Crafted input will lead to Memory allocation failed in dwg_decode_LWPOLYLINE_private (src/dwg.spec:4105)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000003%2Csig:06%2Csrc:000000%2Cop:flip1%2Cpos:43812
ASAN says:
```
==25389==ERROR: AddressSanitizer failed to allocate 0xc9459a000 (54028509184) bytes of LargeMmapAllocator (error code: 12)
==25389==Process memory map follows:
	0x00007fff7000-0x00008fff7000
	0x00008fff7000-0x02008fff7000
	0x02008fff7000-0x10007fff8000
	0x5557879cb000-0x555788ebf000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x5557890bf000-0x5557890d7000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x5557890d7000-0x5557891bb000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x5557891bb000-0x5557891bf000
	....
	0x7fbd7b8fb000-0x7fbd7dc4d000
	0x7fbd7dc4d000-0x7fbd7dc64000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fbd7dc64000-0x7fbd7de63000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fbd7de63000-0x7fbd7de64000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fbd7de64000-0x7fbd7de65000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7fbd7de65000-0x7fbd7de7f000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fbd7de7f000-0x7fbd7e07e000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fbd7e07e000-0x7fbd7e07f000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fbd7e07f000-0x7fbd7e080000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7fbd7e080000-0x7fbd7e084000
	0x7fbd7e084000-0x7fbd7e08b000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fbd7e08b000-0x7fbd7e28a000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fbd7e28a000-0x7fbd7e28b000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fbd7e28b000-0x7fbd7e28c000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7fbd7e28c000-0x7fbd7e28f000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fbd7e28f000-0x7fbd7e48e000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fbd7e48e000-0x7fbd7e48f000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fbd7e48f000-0x7fbd7e490000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7fbd7e490000-0x7fbd7e677000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fbd7e677000-0x7fbd7e877000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fbd7e877000-0x7fbd7e87b000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fbd7e87b000-0x7fbd7e87d000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7fbd7e87d000-0x7fbd7e881000
	0x7fbd7e881000-0x7fbd7ea1e000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fbd7ea1e000-0x7fbd7ec1d000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fbd7ec1d000-0x7fbd7ec1e000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fbd7ec1e000-0x7fbd7ec1f000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7fbd7ec1f000-0x7fbd7ed6f000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fbd7ed6f000-0x7fbd7ef6f000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fbd7ef6f000-0x7fbd7ef72000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fbd7ef72000-0x7fbd7ef75000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7fbd7ef75000-0x7fbd7fbda000
	0x7fbd7fbda000-0x7fbd7fc01000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fbd7fc6d000-0x7fbd7fdf7000
	0x7fbd7fdf7000-0x7fbd7fe01000
	0x7fbd7fe01000-0x7fbd7fe02000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fbd7fe02000-0x7fbd7fe03000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7fbd7fe03000-0x7fbd7fe04000
	0x7ffe9b3e2000-0x7ffe9b403000	[stack]
	0x7ffe9b56a000-0x7ffe9b56d000	[vvar]
	0x7ffe9b56d000-0x7ffe9b56f000	[vdso]
	0xffffffffff600000-0xffffffffff601000	[vsyscall]
==25389==End of process memory map.
==25389==AddressSanitizer CHECK failed: ../../../../src/libsanitizer/sanitizer_common/sanitizer_common.cc:118 "((0 && "unable to mmap")) != (0)" (0x0, 0x0)
    #0 0x7fbd7ed08c02  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xe9c02)
    #1 0x7fbd7ed27595 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x108595)
    #2 0x7fbd7ed12492  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xf3492)
    #3 0x7fbd7ed1e8a5  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xff8a5)
    #4 0x7fbd7ec4b8f1  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2c8f1)
    #5 0x7fbd7ec4604b  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2704b)
    #6 0x7fbd7ecfdd00 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded00)
    #7 0x55578802f729 in dwg_decode_LWPOLYLINE_private ../../src/dwg.spec:4105
    #8 0x555788038884 in dwg_decode_LWPOLYLINE ../../src/dwg.spec:4029
    #9 0x5557883c72f6 in dwg_decode_add_object ../../src/decode.c:4905
    #10 0x5557883daf28 in decode_R13_R2000 ../../src/decode.c:1216
    #11 0x55578840d61a in dwg_decode ../../src/decode.c:239
    #12 0x555787daff7a in dwg_read_file ../../src/dwg.c:206
    #13 0x555787dae32d in main ../../programs/dwg2dxf.c:255
    #14 0x7fbd7e4b1b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #15 0x555787daf2e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)
```

---

Comment by linhlhq on 2019-12-24 03:45:15+00:00:
**3.Crafted input will lead to Memory allocation failed in decode_3dsolid (src/dwg.spec:1801)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000006%2Csig:06%2Csrc:000000%2Cop:flip1%2Cpos:46085
ASAN says:
```
==833==ERROR: AddressSanitizer failed to allocate 0x7f940f9000 (547944894464) bytes of LargeMmapAllocator (error code: 12)
==833==Process memory map follows:
	0x00007fff7000-0x00008fff7000
	0x00008fff7000-0x02008fff7000
	0x02008fff7000-0x10007fff8000
	0x562cd50b0000-0x562cd65a4000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x562cd67a4000-0x562cd67bc000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x562cd67bc000-0x562cd68a0000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x562cd68a0000-0x562cd68a4000
	....
	0x7f7e1e3c9000-0x7f7e2071b000
	0x7f7e2071b000-0x7f7e20732000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f7e20732000-0x7f7e20931000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f7e20931000-0x7f7e20932000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f7e20932000-0x7f7e20933000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f7e20933000-0x7f7e2094d000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f7e2094d000-0x7f7e20b4c000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f7e20b4c000-0x7f7e20b4d000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f7e20b4d000-0x7f7e20b4e000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f7e20b4e000-0x7f7e20b52000
	0x7f7e20b52000-0x7f7e20b59000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f7e20b59000-0x7f7e20d58000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f7e20d58000-0x7f7e20d59000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f7e20d59000-0x7f7e20d5a000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f7e20d5a000-0x7f7e20d5d000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f7e20d5d000-0x7f7e20f5c000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f7e20f5c000-0x7f7e20f5d000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f7e20f5d000-0x7f7e20f5e000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f7e20f5e000-0x7f7e21145000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f7e21145000-0x7f7e21345000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f7e21345000-0x7f7e21349000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f7e21349000-0x7f7e2134b000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f7e2134b000-0x7f7e2134f000
	0x7f7e2134f000-0x7f7e214ec000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f7e214ec000-0x7f7e216eb000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f7e216eb000-0x7f7e216ec000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f7e216ec000-0x7f7e216ed000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f7e216ed000-0x7f7e2183d000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f7e2183d000-0x7f7e21a3d000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f7e21a3d000-0x7f7e21a40000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f7e21a40000-0x7f7e21a43000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f7e21a43000-0x7f7e226a8000
	0x7f7e226a8000-0x7f7e226cf000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f7e2273b000-0x7f7e228c5000
	0x7f7e228c5000-0x7f7e228cf000
	0x7f7e228cf000-0x7f7e228d0000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f7e228d0000-0x7f7e228d1000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f7e228d1000-0x7f7e228d2000
	0x7ffec2458000-0x7ffec2479000	[stack]
	0x7ffec24f6000-0x7ffec24f9000	[vvar]
	0x7ffec24f9000-0x7ffec24fb000	[vdso]
	0xffffffffff600000-0xffffffffff601000	[vsyscall]
==833==End of process memory map.
==833==AddressSanitizer CHECK failed: ../../../../src/libsanitizer/sanitizer_common/sanitizer_common.cc:118 "((0 && "unable to mmap")) != (0)" (0x0, 0x0)
    #0 0x7f7e217d6c02  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xe9c02)
    #1 0x7f7e217f5595 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x108595)
    #2 0x7f7e217e0492  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xf3492)
    #3 0x7f7e217ec8a5  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xff8a5)
    #4 0x7f7e217198f1  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2c8f1)
    #5 0x7f7e2171404b  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2704b)
    #6 0x7f7e217cbd00 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded00)
    #7 0x562cd58a523f in decode_3dsolid ../../src/dwg.spec:1801
    #8 0x562cd58c27dc in dwg_decode_REGION_private ../../src/dwg.spec:2042
    #9 0x562cd58c3123 in dwg_decode_REGION ../../src/dwg.spec:2040
    #10 0x562cd5aa9c06 in dwg_decode_add_object ../../src/decode.c:4741
    #11 0x562cd5abff28 in decode_R13_R2000 ../../src/decode.c:1216
    #12 0x562cd5af261a in dwg_decode ../../src/decode.c:239
    #13 0x562cd5494f7a in dwg_read_file ../../src/dwg.c:206
    #14 0x562cd549332d in main ../../programs/dwg2dxf.c:255
    #15 0x7f7e20f7fb96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #16 0x562cd54942e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)
```

---

Comment by linhlhq on 2019-12-24 03:45:28+00:00:
**4.Crafted input will lead to Memory allocation failed in dwg_decode_HATCH_private (src/dwg.spec:3774)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000009%2Csig:06%2Csrc:000000%2Cop:flip1%2Cpos:47573
ASAN says:
```
==27930==ERROR: AddressSanitizer failed to allocate 0xc7b60b000 (53609541632) bytes of LargeMmapAllocator (error code: 12)
==27930==Process memory map follows:
	0x00007fff7000-0x00008fff7000
	0x00008fff7000-0x02008fff7000
	0x02008fff7000-0x10007fff8000
	0x5572ffa32000-0x557300f26000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x557301126000-0x55730113e000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x55730113e000-0x557301222000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x557301222000-0x557301226000
	....
	0x7f1f63cfe000-0x7f1f66050000
	0x7f1f66050000-0x7f1f66067000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f1f66067000-0x7f1f66266000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f1f66266000-0x7f1f66267000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f1f66267000-0x7f1f66268000	/lib/x86_64-linux-gnu/libgcc_s.so.1
	0x7f1f66268000-0x7f1f66282000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f1f66282000-0x7f1f66481000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f1f66481000-0x7f1f66482000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f1f66482000-0x7f1f66483000	/lib/x86_64-linux-gnu/libpthread-2.27.so
	0x7f1f66483000-0x7f1f66487000
	0x7f1f66487000-0x7f1f6648e000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f1f6648e000-0x7f1f6668d000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f1f6668d000-0x7f1f6668e000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f1f6668e000-0x7f1f6668f000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f1f6668f000-0x7f1f66692000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f1f66692000-0x7f1f66891000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f1f66891000-0x7f1f66892000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f1f66892000-0x7f1f66893000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f1f66893000-0x7f1f66a7a000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f1f66a7a000-0x7f1f66c7a000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f1f66c7a000-0x7f1f66c7e000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f1f66c7e000-0x7f1f66c80000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f1f66c80000-0x7f1f66c84000
	0x7f1f66c84000-0x7f1f66e21000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f1f66e21000-0x7f1f67020000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f1f67020000-0x7f1f67021000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f1f67021000-0x7f1f67022000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f1f67022000-0x7f1f67172000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f1f67172000-0x7f1f67372000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f1f67372000-0x7f1f67375000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f1f67375000-0x7f1f67378000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f1f67378000-0x7f1f67fdd000
	0x7f1f67fdd000-0x7f1f68004000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f1f68070000-0x7f1f681fa000
	0x7f1f681fa000-0x7f1f68204000
	0x7f1f68204000-0x7f1f68205000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f1f68205000-0x7f1f68206000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f1f68206000-0x7f1f68207000
	0x7fffaaf12000-0x7fffaaf33000	[stack]
	0x7fffaafac000-0x7fffaafaf000	[vvar]
	0x7fffaafaf000-0x7fffaafb1000	[vdso]
	0xffffffffff600000-0xffffffffff601000	[vsyscall]
==27930==End of process memory map.
==27930==AddressSanitizer CHECK failed: ../../../../src/libsanitizer/sanitizer_common/sanitizer_common.cc:118 "((0 && "unable to mmap")) != (0)" (0x0, 0x0)
    #0 0x7f1f6710bc02  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xe9c02)
    #1 0x7f1f6712a595 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x108595)
    #2 0x7f1f67115492  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xf3492)
    #3 0x7f1f671218a5  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xff8a5)
    #4 0x7f1f6704e8f1  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2c8f1)
    #5 0x7f1f6704904b  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2704b)
    #6 0x7f1f67100d00 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded00)
    #7 0x5573003a30c8 in dwg_decode_HATCH_private ../../src/dwg.spec:3774
    #8 0x5573003ca0fb in dwg_decode_HATCH ../../src/dwg.spec:3641
    #9 0x557300430ce6 in dwg_decode_add_object ../../src/decode.c:4908
    #10 0x557300441f28 in decode_R13_R2000 ../../src/decode.c:1216
    #11 0x55730047461a in dwg_decode ../../src/decode.c:239
    #12 0x5572ffe16f7a in dwg_read_file ../../src/dwg.c:206
    #13 0x5572ffe1532d in main ../../programs/dwg2dxf.c:255
    #14 0x7f1f668b4b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #15 0x5572ffe162e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)
```

---

Comment by linhlhq on 2019-12-24 03:46:08+00:00:
**5.Double-free in dwg_free (src/free.c:837)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000002%2Csig:06%2Csrc:000093%2Cop:havoc%2Crep:8
ASAN says:
```
==10100==ERROR: AddressSanitizer: attempting double-free on 0x603000000040 in thread T0:
    #0 0x7f6b9a47a7b8 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8)
    #1 0x55b7ed1d1623 in dwg_free ../../src/free.c:837
    #2 0x55b7eca06193 in main ../../programs/dwg2dxf.c:342
    #3 0x7f6b99c2eb96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #4 0x55b7eca072e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x603000000040 is located 0 bytes inside of 32-byte region [0x603000000040,0x603000000060)
freed by thread T0 here:
    #0 0x7f6b9a47a7b8 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8)
    #1 0x55b7ece0c199 in dwg_decode_handleref ../../src/decode.c:3689

previously allocated by thread T0 here:
    #0 0x7f6b9a47ad38 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded38)
    #1 0x55b7ece0bcbd in dwg_decode_handleref ../../src/decode.c:3669
    #2 0x10effffffffff  (<unknown module>)

SUMMARY: AddressSanitizer: double-free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8) in __interceptor_free
==10100==ABORTING

```

---

Comment by linhlhq on 2019-12-24 03:47:41+00:00:
**6.Heap-use-after-free in resolve_objectref_vector (src/decode.c:1434)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000006%2Csig:06%2Csrc:000308%2B000975%2Cop:splice%2Crep:64
ASAN says:
```
==25001==ERROR: AddressSanitizer: heap-use-after-free on address 0x603000000058 at pc 0x55e4585b3686 bp 0x7ffc01783e70 sp 0x7ffc01783e60
READ of size 8 at 0x603000000058 thread T0
    #0 0x55e4585b3685 in resolve_objectref_vector ../../src/decode.c:1434
    #1 0x55e458b6fa26 in decode_R13_R2000 ../../src/decode.c:1421
    #2 0x55e458b9e61a in dwg_decode ../../src/decode.c:239
    #3 0x55e458540f7a in dwg_read_file ../../src/dwg.c:206
    #4 0x55e45853f32d in main ../../programs/dwg2dxf.c:255
    #5 0x7f0bd1d26b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #6 0x55e4585402e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x603000000058 is located 24 bytes inside of 32-byte region [0x603000000040,0x603000000060)
freed by thread T0 here:
    #0 0x7f0bd25727b8 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8)
    #1 0x55e458945199 in dwg_decode_handleref ../../src/decode.c:3689

previously allocated by thread T0 here:
    #0 0x7f0bd2572d38 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded38)
    #1 0x55e458944cbd in dwg_decode_handleref ../../src/decode.c:3669
    #2 0x10effffffffff  (<unknown module>)

SUMMARY: AddressSanitizer: heap-use-after-free ../../src/decode.c:1434 in resolve_objectref_vector
Shadow bytes around the buggy address:
  0x0c067fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c067fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c067fff8000: fa fa fd fd fd fd fa fa fd fd fd[fd]fa fa 00 00
  0x0c067fff8010: 00 00 fa fa 00 00 00 00 fa fa 00 00 00 00 fa fa
  0x0c067fff8020: fd fd fd fd fa fa fd fd fd fd fa fa 00 00 00 02
  0x0c067fff8030: fa fa 00 00 00 02 fa fa 00 00 00 03 fa fa fa fa
  0x0c067fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c067fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 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
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  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
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==25001==ABORTING
```

---

Comment by linhlhq on 2019-12-24 03:48:07+00:00:
**7.Heap-buffer-overflow in decode_R13_R2000 (src/decode.c:1315)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000007%2Csig:06%2Csrc:000316%2B000377%2Cop:splice%2Crep:128
ASAN says:
```
==17430==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6130000001b0 at pc 0x5647424fb76d bp 0x7ffdbd213570 sp 0x7ffdbd213560
READ of size 8 at 0x6130000001b0 thread T0
    #0 0x5647424fb76c in decode_R13_R2000 ../../src/decode.c:1315
    #1 0x56474251561a in dwg_decode ../../src/decode.c:239
    #2 0x564741eb7f7a in dwg_read_file ../../src/dwg.c:206
    #3 0x564741eb632d in main ../../programs/dwg2dxf.c:255
    #4 0x7f94848bcb96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #5 0x564741eb72e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x6130000001b0 is located 8 bytes to the right of 360-byte region [0x613000000040,0x6130000001a8)
allocated by thread T0 here:
    #0 0x7f9485108d38 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded38)
    #1 0x5647424dea59 in decode_R13_R2000 ../../src/decode.c:861

SUMMARY: AddressSanitizer: heap-buffer-overflow ../../src/decode.c:1315 in decode_R13_R2000
Shadow bytes around the buggy address:
  0x0c267fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c267fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c267fff8000: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x0c267fff8010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c267fff8020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c267fff8030: 00 00 00 00 00 fa[fa]fa fa fa fa fa fa fa fa fa
  0x0c267fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c267fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c267fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c267fff8070: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c267fff8080: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 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
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  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
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==17430==ABORTING
```

---

Comment by linhlhq on 2019-12-24 03:48:30+00:00:
**8.Crafted input will lead to Memory allocation failed in decode_preR13_section (src/decode.c:315)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000008%2Csig:06%2Csrc:000768%2B000486%2Cop:splice%2Crep:128
ASAN says:
```
==30021==ERROR: AddressSanitizer failed to allocate 0x1138003000 (73953980416) bytes of LargeMmapAllocator (error code: 12)
==30021==Process memory map follows:
	0x00007fff7000-0x00008fff7000
	0x00008fff7000-0x02008fff7000
	0x02008fff7000-0x10007fff8000
	0x555c6a254000-0x555c6b748000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x555c6b948000-0x555c6b960000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	0x555c6b960000-0x555c6ba44000	/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf
	....
	0x7f552f888000-0x7f552f88f000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f552f88f000-0x7f552fa8e000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f552fa8e000-0x7f552fa8f000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f552fa8f000-0x7f552fa90000	/lib/x86_64-linux-gnu/librt-2.27.so
	0x7f552fa90000-0x7f552fa93000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f552fa93000-0x7f552fc92000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f552fc92000-0x7f552fc93000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f552fc93000-0x7f552fc94000	/lib/x86_64-linux-gnu/libdl-2.27.so
	0x7f552fc94000-0x7f552fe7b000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f552fe7b000-0x7f553007b000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f553007b000-0x7f553007f000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f553007f000-0x7f5530081000	/lib/x86_64-linux-gnu/libc-2.27.so
	0x7f5530081000-0x7f5530085000
	0x7f5530085000-0x7f5530222000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f5530222000-0x7f5530421000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f5530421000-0x7f5530422000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f5530422000-0x7f5530423000	/lib/x86_64-linux-gnu/libm-2.27.so
	0x7f5530423000-0x7f5530573000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f5530573000-0x7f5530773000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f5530773000-0x7f5530776000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f5530776000-0x7f5530779000	/usr/lib/x86_64-linux-gnu/libasan.so.4.0.0
	0x7f5530779000-0x7f55313de000
	0x7f55313de000-0x7f5531405000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f5531471000-0x7f55315fb000
	0x7f55315fb000-0x7f5531605000
	0x7f5531605000-0x7f5531606000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f5531606000-0x7f5531607000	/lib/x86_64-linux-gnu/ld-2.27.so
	0x7f5531607000-0x7f5531608000
	0x7fff8fdef000-0x7fff8fe10000	[stack]
	0x7fff8fea3000-0x7fff8fea6000	[vvar]
	0x7fff8fea6000-0x7fff8fea8000	[vdso]
	0xffffffffff600000-0xffffffffff601000	[vsyscall]
==30021==End of process memory map.
==30021==AddressSanitizer CHECK failed: ../../../../src/libsanitizer/sanitizer_common/sanitizer_common.cc:118 "((0 && "unable to mmap")) != (0)" (0x0, 0x0)
    #0 0x7f553050cc02  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xe9c02)
    #1 0x7f553052b595 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x108595)
    #2 0x7f5530516492  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xf3492)
    #3 0x7f55305228a5  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xff8a5)
    #4 0x7f553044f8f1  (/usr/lib/x86_64-linux-gnu/libasan.so.4+0x2c8f1)
    #5 0x7f5530501f07 in realloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xdef07)
    #6 0x555c6a380d1f in decode_preR13_section ../../src/decode.c:315
    #7 0x555c6a9fadca in decode_preR13 ../../src/decode.c:708
    #8 0x555c6ac9634f in dwg_decode ../../src/decode.c:235
    #9 0x555c6a638f7a in dwg_read_file ../../src/dwg.c:206
    #10 0x555c6a63732d in main ../../programs/dwg2dxf.c:255
    #11 0x7f552fcb5b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #12 0x555c6a6382e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)
```

---

Comment by linhlhq on 2019-12-24 03:48:51+00:00:
**9.Heap-buffer-overflow in decode_preR13_section (src/decode.c:350)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000024%2Csig:06%2Csrc:002283%2B001622%2Cop:splice%2Crep:64
ASAN says:
```
==31479==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x629000004e14 at pc 0x55713d105f18 bp 0x7ffefe359270 sp 0x7ffefe359260
WRITE of size 4 at 0x629000004e14 thread T0
    #0 0x55713d105f17 in decode_preR13_section ../../src/decode.c:350
    #1 0x55713d77fdca in decode_preR13 ../../src/decode.c:708
    #2 0x55713da1b34f in dwg_decode ../../src/decode.c:235
    #3 0x55713d3bdf7a in dwg_read_file ../../src/dwg.c:206
    #4 0x55713d3bc32d in main ../../programs/dwg2dxf.c:255
    #5 0x7fcb2bc53b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #6 0x55713d3bd2e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x629000004e14 is located 20 bytes to the right of 19456-byte region [0x629000000200,0x629000004e00)
allocated by thread T0 here:
    #0 0x7fcb2c49fb50 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xdeb50)
    #1 0x55713d19562d in decode_preR13_entities ../../src/decode.c:4356

SUMMARY: AddressSanitizer: heap-buffer-overflow ../../src/decode.c:350 in decode_preR13_section
Shadow bytes around the buggy address:
  0x0c527fff8970: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff8980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff8990: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff89a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c527fff89b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c527fff89c0: fa fa[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff89d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff89e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff89f0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff8a00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c527fff8a10: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 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
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  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
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==31479==ABORTING
```

---

Comment by linhlhq on 2019-12-24 03:49:07+00:00:
**10.Heap-buffer-overflow in bit_search_sentinel (src/bits.c:1825)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000041%2Csig:06%2Csrc:003308%2Cop:havoc%2Crep:16
ASAN says:
```
==32322==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7f2638fc53de at pc 0x562bfa36216a bp 0x7ffc67dcbdc0 sp 0x7ffc67dcbdb0
READ of size 1 at 0x7f2638fc53de thread T0
    #0 0x562bfa362169 in bit_search_sentinel ../../src/bits.c:1825
    #1 0x562bfa9264ac in decode_R13_R2000 ../../src/decode.c:1389
    #2 0x562bfa95261a in dwg_decode ../../src/decode.c:239
    #3 0x562bfa2f4f7a in dwg_read_file ../../src/dwg.c:206
    #4 0x562bfa2f332d in main ../../programs/dwg2dxf.c:255
    #5 0x7f2637792b96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #6 0x562bfa2f42e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x7f2638fc53de is located 0 bytes to the right of 400350-byte region [0x7f2638f63800,0x7f2638fc53de)
allocated by thread T0 here:
    #0 0x7f2637fded38 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded38)
    #1 0x562bfa2f4e61 in dat_read_file ../../src/dwg.c:69
    #2 0x562bfa2f4e61 in dwg_read_file ../../src/dwg.c:199

SUMMARY: AddressSanitizer: heap-buffer-overflow ../../src/bits.c:1825 in bit_search_sentinel
Shadow bytes around the buggy address:
  0x0fe5471f0a20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe5471f0a30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe5471f0a40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe5471f0a50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe5471f0a60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0fe5471f0a70: 00 00 00 00 00 00 00 00 00 00 00[06]fa fa fa fa
  0x0fe5471f0a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe5471f0a90: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe5471f0aa0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe5471f0ab0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe5471f0ac0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 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
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  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
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==32322==ABORTING
```

---

Comment by rurban on 2019-12-24 14:02:49+00:00:
I can repro all

---

Comment by rurban on 2019-12-24 14:46:34+00:00:
I'll ignore the preR13 error (id 000008), as this code is not stable yet, and disabled in releases.

---

Comment by linhlhq on 2019-12-25 02:02:26+00:00:
Yes, when you fix all the bugs in the release I will come back.

---

Comment by rurban on 2019-12-25 08:50:29+00:00:
Done in the `smoke/fuzz` branch

---

Comment by linhlhq on 2019-12-25 10:06:25+00:00:
Did you fix all the bugs I reported above? Except for bug **8. lead to Memory allocation failed in decode_preR13_section**

---

Comment by rurban on 2019-12-25 11:04:40+00:00:
All fixed now

---

Comment by linhlhq on 2019-12-25 13:40:12+00:00:
yeah, that was awesome. Can you help me request cve for the above bugs? Thank you.

---

Comment by rurban on 2019-12-25 14:15:46+00:00:
You cannot CVE's for the preR13 bugs, because that code is disabled with releases. 

---

Comment by linhlhq on 2019-12-25 15:24:54+00:00:
@rurban So are there any other bugs you can help me with? With bugs from 1 to 7 I report above.

---

Comment by attritionorg on 2019-12-25 18:54:54+00:00:
@rurban Can you cliff notes if any of them were in active code and link to the fixing commits?

---

Comment by nluedtke on 2019-12-30 15:02:10+00:00:
It appears these were assigned:
- [CVE-2019-20009](https://nvd.nist.gov/vuln/detail/CVE-2019-20009)
- [CVE-2019-20010](https://nvd.nist.gov/vuln/detail/CVE-2019-20010)
- [CVE-2019-20011](https://nvd.nist.gov/vuln/detail/CVE-2019-20011)
- [CVE-2019-20012](https://nvd.nist.gov/vuln/detail/CVE-2019-20012)
- [CVE-2019-20013](https://nvd.nist.gov/vuln/detail/CVE-2019-20013)
- [CVE-2019-20014](https://nvd.nist.gov/vuln/detail/CVE-2019-20014)
- [CVE-2019-20015](https://nvd.nist.gov/vuln/detail/CVE-2019-20015)

---

Comment by rurban on 2019-12-30 18:26:00+00:00:
Thanks, I'll have to mark them as fixed by the latest release 0.9.3

---

Comment by linhlhq on 2020-01-01 10:21:16+00:00:
@rurban Can I request cve for preR13 bugs? Or can you request for me? Thanks.

---

Comment by rurban on 2020-01-01 13:02:54+00:00:
These cannot be CVE's as this code is disabled in releases.

linhlhq <notifications@github.com> schrieb am Mi., 1. Jan. 2020, 11:21:

> @rurban <https://github.com/rurban> Can I request cve for preR13 bugs? Or
> can you request for me? Thanks.
>
> —
> You are receiving this because you were mentioned.
> Reply to this email directly, view it on GitHub
> <https://github.com/LibreDWG/libredwg/issues/176?email_source=notifications&email_token=AAAKGUKXAWN4WBUHYJMUTPLQ3RVBZA5CNFSM4J62I26KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEH5CARI#issuecomment-570040389>,
> or unsubscribe
> <https://github.com/notifications/unsubscribe-auth/AAAKGULY6L3JRIK6R662AMLQ3RVBZANCNFSM4J62I26A>
> .
>


---

Comment by rurban on 2020-01-01 14:58:46+00:00:
Verified them to be fixed with 3f515d52954e2ec009a2508d3d5be04e3bcc094b (for the upcoming 0.10) also

Commit References:
3f515d52954e2ec009a2508d3d5be04e3bcc094b

================= Bug Report (2/2) ==================
## Source: GitHub Issue
## URL: https://github.com/LibreDWG/libredwg/issues/176#issuecomment-568643172
## Description:
Issue: LibreDWG/libredwg#176
Title: Several bugs found by fuzzing
Referenced comment by linhlhq on 2019-12-24 03:46:08+00:00:

**5.Double-free in dwg_free (src/free.c:837)**
PoC: https://github.com/linhlhq/research/blob/master/PoCs/libreDWG/id:000002%2Csig:06%2Csrc:000093%2Cop:havoc%2Crep:8
ASAN says:
```
==10100==ERROR: AddressSanitizer: attempting double-free on 0x603000000040 in thread T0:
    #0 0x7f6b9a47a7b8 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8)
    #1 0x55b7ed1d1623 in dwg_free ../../src/free.c:837
    #2 0x55b7eca06193 in main ../../programs/dwg2dxf.c:342
    #3 0x7f6b99c2eb96 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21b96)
    #4 0x55b7eca072e9 in _start (/home/user/linhlhq/libredwg/obj-afl/programs/dwg2dxf+0x3e42e9)

0x603000000040 is located 0 bytes inside of 32-byte region [0x603000000040,0x603000000060)
freed by thread T0 here:
    #0 0x7f6b9a47a7b8 in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8)
    #1 0x55b7ece0c199 in dwg_decode_handleref ../../src/decode.c:3689

previously allocated by thread T0 here:
    #0 0x7f6b9a47ad38 in __interceptor_calloc (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xded38)
    #1 0x55b7ece0bcbd in dwg_decode_handleref ../../src/decode.c:3669
    #2 0x10effffffffff  (<unknown module>)

SUMMARY: AddressSanitizer: double-free (/usr/lib/x86_64-linux-gnu/libasan.so.4+0xde7b8) in __interceptor_free
==10100==ABORTING

```

Build script:
#!/bin/bash -eu
# Minimized build script with only core build commands
set -eu
sh ./autogen.sh
./configure --disable-shared
make -j$(nproc)

Dockerfile:
FROM hwiwonlee/secb.base:latest
RUN apt-get update && apt-get install -y autoconf libtool texinfo
RUN git clone https://github.com/libredwg/libredwg libredwg
RUN git -C libredwg checkout 5c4464ef38776addf64b2648d20d4eeb3c4a0082
WORKDIR $SRC/libredwg
COPY build.sh $SRC/

Additional files:
filename: fuzz_dwg_decode.options
content: [libfuzzer]
detect_leaks=0