bugThe FreeType Project - Bugs: bug #43658, FreeType 2.5.3 CFF CharString...

 
 

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bug #43658: FreeType 2.5.3 CFF CharString parsing heap-based buffer overflow in "cff_builder_add_point"

Submitter:  Mateusz Jurczyk <j00ru>
Submitted:  Fri 21 Nov 2014 11:34:42 AM UTC
   
 
Severity:  3 - Normal Item Group:  Crash
Status:  Fixed Privacy:  Public
Assigned to:  wl Open/Closed:  Closed
Planned Release:  2.5.4

Sat 22 Nov 2014 08:17:36 AM UTC, comment #1: 

Fixed in git.  Thanks for the report!

 Werner LEMBERG <wl>
Group administrator
Fri 21 Nov 2014 11:34:42 AM UTC, original submission:  

The following heap-based out-of-bounds memory write has been encountered in FreeType while fuzzing OTF fonts. It has been reproduced with the current version of freetype2 from master git branch, with a 64-bit build of the ftbench utility compiled with AddressSanitizer:

$ ftbench <file>

Attached are three POC files which trigger the condition.

=================================================================
==5718==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7f4736a69780 at pc 0x741f52 bp 0x7fff23cea610 sp 0x7fff23cea608
WRITE of size 8 at 0x7f4736a69780 thread T0
    #0 0x741f51 in cff_builder_add_point freetype2/src/cff/cffgload.c:504
    #1 0x7409eb in cf2_builder_cubeTo freetype2/src/cff/cf2ft.c:197
    #2 0x72977a in cf2_glyphpath_pushPrevElem freetype2/src/cff/cf2hints.c:1336
    #3 0x70820a in cf2_glyphpath_curveTo freetype2/src/cff/cf2hints.c:1782
    #4 0x6f0f5c in cf2_interpT2CharString freetype2/src/cff/cf2intrp.c:720
    #5 0x6e8570 in cf2_getGlyphOutline freetype2/src/cff/cf2font.c:469
    #6 0x6e4c5e in cf2_decoder_parse_charstrings freetype2/src/cff/cf2ft.c:367
    #7 0x6da446 in cff_slot_load freetype2/src/cff/cffgload.c:2840
    #8 0x69dbcc in cff_glyph_load freetype2/src/cff/cffdrivr.c:185
    #9 0x4a427e in FT_Load_Glyph freetype2/src/base/ftobjs.c:726
    #10 0x491d69 in test_load ft2demos-2.5.3/src/ftbench.c:249
    #11 0x492b51 in benchmark ft2demos-2.5.3/src/ftbench.c:216
    #12 0x48e962 in main ft2demos-2.5.3/src/ftbench.c:1020

0x7f4736a69780 is located 0 bytes to the right of 524160-byte region [0x7f47369e9800,0x7f4736a69780)
allocated by thread T0 here:
    #0 0x47231b in realloc (ft2demos-2.5.3/bin/ftbench+0x47231b)
    #1 0xaf2961 in ft_realloc freetype2/src/base/ftsystem.c:107
    #2 0x5359a6 in ft_mem_qrealloc freetype2/src/base/ftutil.c:155
    #3 0x4b1331 in ft_mem_realloc freetype2/src/base/ftutil.c:102
    #4 0x4b2cfe in FT_GlyphLoader_CheckPoints freetype2/src/base/ftgloadr.c:225
    #5 0x7417e6 in cff_check_points freetype2/src/cff/cffgload.c:472
    #6 0x7408f1 in cf2_builder_cubeTo freetype2/src/cff/cf2ft.c:195
    #7 0x72977a in cf2_glyphpath_pushPrevElem freetype2/src/cff/cf2hints.c:1336
    #8 0x70820a in cf2_glyphpath_curveTo freetype2/src/cff/cf2hints.c:1782
    #9 0x6f0f5c in cf2_interpT2CharString freetype2/src/cff/cf2intrp.c:720
    #10 0x6e8570 in cf2_getGlyphOutline freetype2/src/cff/cf2font.c:469
    #11 0x6e4c5e in cf2_decoder_parse_charstrings freetype2/src/cff/cf2ft.c:367
    #12 0x6da446 in cff_slot_load freetype2/src/cff/cffgload.c:2840
    #13 0x69dbcc in cff_glyph_load freetype2/src/cff/cffdrivr.c:185
    #14 0x4a427e in FT_Load_Glyph freetype2/src/base/ftobjs.c:726
    #15 0x491d69 in test_load ft2demos-2.5.3/src/ftbench.c:249
    #16 0x492b51 in benchmark ft2demos-2.5.3/src/ftbench.c:216
    #17 0x48e962 in main ft2demos-2.5.3/src/ftbench.c:1020

SUMMARY: AddressSanitizer: heap-buffer-overflow freetype2/src/cff/cffgload.c:504 cff_builder_add_point
Shadow bytes around the buggy address:
  0x0fe966d452a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe966d452b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe966d452c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe966d452d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fe966d452e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0fe966d452f0:[fa]fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe966d45300: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe966d45310: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe966d45320: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe966d45330: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0fe966d45340: 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
  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
  Contiguous container OOB:fc
  ASan internal:           fe
==5718==ABORTING

 Mateusz Jurczyk <j00ru>
Group Member

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attached Files
file #32503:  asan_heap-oob_7337be_4558_cov_2281824659_combustt.otf added by j00ru (595KiB - application/octet-stream)
file #32504:  asan_heap-oob_7337be_5479_cov_229227555_elsewher.otf added by j00ru (421KiB - application/octet-stream)
file #32505:  asan_heap-oob_7337be_5477_cov_631718262_elsewher.otf added by j00ru (446KiB - application/octet-stream)

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -email is unavailable- added by wl (Posted a comment)
  • -email is unavailable- added by j00ru (Submitted the item)

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    Follow 8 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2014-11-22 wl StatusNone Fixed
        PrivacyPrivate Public
        Assigned toNone wl
        Open/ClosedOpen Closed
        Planned ReleaseNone 2.5.4
    2014-11-21 j00ru Attached File- Added asan_heap-oob_7337be_4558_cov_2281824659_combustt.otf, #32503
        Attached File- Added asan_heap-oob_7337be_5479_cov_229227555_elsewher.otf, #32504
        Attached File- Added asan_heap-oob_7337be_5477_cov_631718262_elsewher.otf, #32505

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