CVE-2020-21683: Xfig / Tickets / #77 global-buffer-overflow in shade_or_tint_name_after_declare_color at genpstricks.c:1135

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Status: closed

Owner: nobody

Labels: None

Updated: 2020-12-21

Created: 2019-12-28

Private: No

Hi,
I found a global-buffer-overflow in shade_or_tint_name_after_declare_color at genpstricks.c:1135
Please run following command to reproduce it,

ASAN LOG

Invalid color number -1674115757 at line 37, using default color. An open polygon at line 38 - close it. ================================================================= ==22079==ERROR: AddressSanitizer: global-buffer-overflow on address 0x000000c5a81c at pc 0x00000080aeb5 bp 0x7ffd1029a770 sp 0x7ffd1029a768 READ of size 4 at 0x000000c5a81c thread T0 #0 0x80aeb4 in shade_or_tint_name_after_declare_color /home/tmp/mcj-fig2dev/fig2dev/dev/genpstricks.c:1135:41 #1 0x80aeb4 in format_options /home/tmp/mcj-fig2dev/fig2dev/dev/genpstricks.c:1859 #2 0x7fa81d in genpstrx_line /home/tmp/mcj-fig2dev/fig2dev/dev/genpstricks.c:2270:7 #3 0x54b8bb in gendev_objects /home/tmp/mcj-fig2dev/fig2dev/fig2dev.c:1003:6 #4 0x54b8bb in main /home/tmp/mcj-fig2dev/fig2dev/fig2dev.c:480 #5 0x7ff8beecdb96 in __libc_start_main /build/glibc-OTsEL5/glibc-2.27/csu/…/csu/libc-start.c:310 #6 0x41b3a9 in _start (/home/tmp/fig2dev+0x41b3a9)

0x000000c5a81c is located 4 bytes to the left of global variable ‘color_table’ defined in ‘genpstricks.c:986:3’ (0xc5a820) of size 34816 0x000000c5a81c is located 44 bytes to the right of global variable ‘dev_pstricks’ defined in ‘genpstricks.c:2851:15’ (0xc5a7a0) of size 80 SUMMARY: AddressSanitizer: global-buffer-overflow /home/tmp/mcj-fig2dev/fig2dev/dev/genpstricks.c:1135:41 in shade_or_tint_name_after_declare_color Shadow bytes around the buggy address: 0x0000801834b0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0000801834c0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0000801834d0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0000801834e0: f9 f9 f9 f9 04 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 0x0000801834f0: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 f9 f9 =>0x000080183500: f9 f9 f9[f9]00 00 00 00 00 00 00 00 00 00 00 00 0x000080183510: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080183520: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080183530: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080183540: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000080183550: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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 ==22079==ABORTING

fig2dev Version 3.2.7b

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