Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Thu, 2 Mar 2017 16:34:17 +0000
From: "Agostino Sarubbo" <ago@...too.org>
To: "oss-security@...ts.openwall.com" <oss-security@...ts.openwall.com>
Subject: podofo: NULL pointer dereference in ColorChanger::GetColorFromStack (colorchanger.cpp)

Description:
podofo is a C++ library to work with the PDF file format.

A fuzz on it discovered a null pointer access. The upstream project denies me to open a new ticket. So, I just will forward this on the -users mailing list.

The complete ASan output:

# podofocolor dummy $FILE foo
==18954==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x00000052302d bp 0x7fc24b8e2000 sp 0x7ffcaaf21810 T0)
==18954==The signal is caused by a READ memory access.
==18954==Hint: address points to the zero page.
    #0 0x52302c in getVtablePrefix /tmp/portage/sys-devel/llvm-3.9.1-r1/work/llvm-3.9.1.src/projects/compiler-rt/lib/ubsan/ubsan_type_hash_itanium.cc:198
    #1 0x52302c in __ubsan::checkDynamicType(void*, void*, unsigned long) /tmp/portage/sys-devel/llvm-3.9.1-r1/work/llvm-3.9.1.src/projects/compiler-rt/lib/ubsan/ubsan_type_hash_itanium.cc:221
    #2 0x521082 in HandleDynamicTypeCacheMiss /tmp/portage/sys-devel/llvm-3.9.1-r1/work/llvm-3.9.1.src/projects/compiler-rt/lib/ubsan/ubsan_handlers_cxx.cc:37
    #3 0x521922 in __ubsan_handle_dynamic_type_cache_miss /tmp/portage/sys-devel/llvm-3.9.1-r1/work/llvm-3.9.1.src/projects/compiler-rt/lib/ubsan/ubsan_handlers_cxx.cc:87
    #4 0x538eb2 in ColorChanger::GetColorFromStack(int, std::vector<PoDoFo::PdfVariant, std::allocator >&) /tmp/portage/app-text/podofo-0.9.5/work/podofo-0.9.5/tools/podofocolor/colorchanger.cpp:430:33
    #5 0x530d50 in ColorChanger::ProcessColor(ColorChanger::EKeywordType, int, std::vector<PoDoFo::PdfVariant, std::allocator >&, GraphicsStack&) 
/tmp/portage/app-text/podofo-0.9.5/work/podofo-0.9.5/tools/podofocolor/colorchanger.cpp:449:28
    #6 0x52c2a9 in ColorChanger::ReplaceColorsInPage(PoDoFo::PdfCanvas*) /tmp/portage/app-text/podofo-0.9.5/work/podofo-0.9.5/tools/podofocolor/colorchanger.cpp:214:31
    #7 0x526921 in ColorChanger::start() /tmp/portage/app-text/podofo-0.9.5/work/podofo-0.9.5/tools/podofocolor/colorchanger.cpp:120:15
    #8 0x523b8d in main /tmp/portage/app-text/podofo-0.9.5/work/podofo-0.9.5/tools/podofocolor/podofocolor.cpp:116:12
    #9 0x7fc2490df78f in __libc_start_main /tmp/portage/sys-libs/glibc-2.23-r3/work/glibc-2.23/csu/../csu/libc-start.c:289
    #10 0x4300e8 in _start (/usr/bin/podofocolor+0x4300e8)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /tmp/portage/sys-devel/llvm-3.9.1-r1/work/llvm-3.9.1.src/projects/compiler-rt/lib/ubsan/ubsan_type_hash_itanium.cc:198 in getVtablePrefix
==18954==ABORTING

Affected version:
0.9.5

Fixed version:
N/A

Commit fix:
N/A

Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.

CVE:
N/A

Reproducer:
https://github.com/asarubbo/poc/blob/master/00217-podofo-nullptr-colorchanger-cpp

Timeline:
2017-03-01: bug discovered
2017-03-02: bug reported upstream
2017-03-02: blog post about the issue

Note:
This bug was found with American Fuzzy Lop.

Permalink:
https://blogs.gentoo.org/ago/2017/03/02/podofo-null-pointer-dereference-in-colorchangergetcolorfromstack-colorchanger-cpp

--
Agostino Sarubbo
Gentoo Linux Developer


Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.