Heap-based Buffer Overflow in function vim_regsub_both in vim/vim
Valid
Reported on
May 25th 2022
Description
Heap-based Buffer Overflow in function vim_regsub_both at regexp.c:1954
vim version
git log
commit 4d97a565ae8be0d4debba04ebd2ac3e75a0c8010 (HEAD -> master, tag: v8.2.5037, origin/master, origin/HEAD)
POC
./vim -u NONE -i NONE -n -m -X -Z -e -s -S /mnt/share/max/fuzz/poc/vim/poc_obw5_s.dat -c :qa!
=================================================================
==2583207==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x606000003595 at pc 0x000000485358 bp 0x7fffffff7230 sp 0x7fffffff69f0
WRITE of size 2 at 0x606000003595 thread T0
#0 0x485357 in strcpy (/home/fuzz/fuzz/vim/vim/src/vim+0x485357)
#1 0xced574 in vim_regsub_both /home/fuzz/fuzz/vim/vim/src/regexp.c:1954:3
#2 0xcf1973 in vim_regsub_multi /home/fuzz/fuzz/vim/vim/src/regexp.c:1897:14
#3 0x7b4663 in ex_substitute /home/fuzz/fuzz/vim/vim/src/ex_cmds.c:4529:9
#4 0x7dd699 in do_one_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:2568:2
#5 0x7ca405 in do_cmdline /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:992:17
#6 0xe5998c in do_source_ext /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1674:5
#7 0xe563e6 in do_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1801:12
#8 0xe55d1c in cmd_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1174:14
#9 0xe553fe in ex_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1200:2
#10 0x7dd699 in do_one_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:2568:2
#11 0x7ca405 in do_cmdline /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:992:17
#12 0x7cf0a1 in do_cmdline_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:586:12
#13 0x14258e2 in exe_commands /home/fuzz/fuzz/vim/vim/src/main.c:3106:2
#14 0x1421a7b in vim_main2 /home/fuzz/fuzz/vim/vim/src/main.c:780:2
#15 0x1417175 in main /home/fuzz/fuzz/vim/vim/src/main.c:432:12
#16 0x7ffff7bec082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
#17 0x41ea6d in _start (/home/fuzz/fuzz/vim/vim/src/vim+0x41ea6d)
0x606000003595 is located 0 bytes to the right of 53-byte region [0x606000003560,0x606000003595)
allocated by thread T0 here:
#0 0x499ccd in malloc (/home/fuzz/fuzz/vim/vim/src/vim+0x499ccd)
#1 0x4cb3aa in lalloc /home/fuzz/fuzz/vim/vim/src/alloc.c:246:11
#2 0x4cb28a in alloc /home/fuzz/fuzz/vim/vim/src/alloc.c:151:12
#3 0x7b42c7 in ex_substitute /home/fuzz/fuzz/vim/vim/src/ex_cmds.c:4491:24
#4 0x7dd699 in do_one_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:2568:2
#5 0x7ca405 in do_cmdline /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:992:17
#6 0xe5998c in do_source_ext /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1674:5
#7 0xe563e6 in do_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1801:12
#8 0xe55d1c in cmd_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1174:14
#9 0xe553fe in ex_source /home/fuzz/fuzz/vim/vim/src/scriptfile.c:1200:2
#10 0x7dd699 in do_one_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:2568:2
#11 0x7ca405 in do_cmdline /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:992:17
#12 0x7cf0a1 in do_cmdline_cmd /home/fuzz/fuzz/vim/vim/src/ex_docmd.c:586:12
#13 0x14258e2 in exe_commands /home/fuzz/fuzz/vim/vim/src/main.c:3106:2
#14 0x1421a7b in vim_main2 /home/fuzz/fuzz/vim/vim/src/main.c:780:2
#15 0x1417175 in main /home/fuzz/fuzz/vim/vim/src/main.c:432:12
#16 0x7ffff7bec082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
SUMMARY: AddressSanitizer: heap-buffer-overflow (/home/fuzz/fuzz/vim/vim/src/vim+0x485357) in strcpy
Shadow bytes around the buggy address:
0x0c0c7fff8660: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
0x0c0c7fff8670: fd fd fd fd fd fd fd fd fa fa fa fa 00 00 00 00
0x0c0c7fff8680: 00 00 02 fa fa fa fa fa fd fd fd fd fd fd fd fd
0x0c0c7fff8690: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
0x0c0c7fff86a0: 00 00 00 00 00 00 02 fa fa fa fa fa 00 00 00 00
=>0x0c0c7fff86b0: 00 00[05]fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff86c0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff86d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff86e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff86f0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff8700: 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
Shadow gap: cc
==2583207==ABORTING
Impact
This may result in corruption of sensitive information, a crash, or code execution among other things.
We are processing your report and will contact the
vim
team within 24 hours.
2 years ago
We have contacted a member of the
vim
team and are waiting to hear back
2 years ago
I cannot reproduce this problem. Please sync to head, it might have already been fixed by Patch 8.2.5007
Hmm, your comment "tag: v8.2.5014" indicates that patch 8.2.5007 would already be included. Nevertheless, I cannot reproduce.
Uinitech modified the report
2 years ago
Found another Heap-based Buffer Overflow at regexp.c:1954 after sync to head(tag: v8.2.5037). Wish you could reproduce this one. Report is modified accordingly
We have sent a
follow up to the
vim
team.
We will try again in 7 days.
2 years ago
Yes, this one I can reproduce. The POC can be simplified a bit more and I'll use that for a test.
The researcher's credibility has increased: +7
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