Description:
podofo is a C++ library to work with the PDF file format.
A fuzz on it discovered a null pointer dereference. 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
==9554==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x0000004ca47d bp 0x7fff58eb6bb0 sp 0x7fff58eb6330 T0)
==9554==The signal is caused by a READ memory access.
==9554==Hint: address points to the zero page.
#0 0x4ca47c in AddressIsPoisoned /tmp/portage/sys-devel/llvm-3.9.0-r1/work/llvm-3.9.0.src/projects/compiler-rt/lib/asan/asan_mapping.h:321
#1 0x4ca47c in QuickCheckForUnpoisonedRegion /tmp/portage/sys-devel/llvm-3.9.0-r1/work/llvm-3.9.0.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:43
#2 0x4ca47c in __asan_memcpy /tmp/portage/sys-devel/llvm-3.9.0-r1/work/llvm-3.9.0.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:413
#3 0x7f5fc924b58d in PoDoFo::PdfColor::operator=(PoDoFo::PdfColor const&) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfColor.cpp:575:9
#4 0x52d31f in GraphicsStack::TGraphicsStackElement::operator=(GraphicsStack::TGraphicsStackElement const&) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/graphicsstack.h:46:29
#5 0x52d31f in GraphicsStack::TGraphicsStackElement::TGraphicsStackElement(GraphicsStack::TGraphicsStackElement const&) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/graphicsstack.h:41
#6 0x52c46a in GraphicsStack::Push() /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/graphicsstack.cpp:40:27
#7 0x522005 in ColorChanger::ReplaceColorsInPage(PoDoFo::PdfCanvas*) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/colorchanger.cpp:187:35
#8 0x51ed8e in ColorChanger::start() /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/colorchanger.cpp:120:15
#9 0x51c06d in main /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofocolor/podofocolor.cpp:116:12
#10 0x7f5fc7d3261f in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.22-r4/work/glibc-2.22/csu/libc-start.c:289
#11 0x428718 in _start (/usr/bin/podofocolor+0x428718)
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /tmp/portage/sys-devel/llvm-3.9.0-r1/work/llvm-3.9.0.src/projects/compiler-rt/lib/asan/asan_mapping.h:321 in AddressIsPoisoned
==9554==ABORTING
Affected version:
0.9.4
Fixed version:
N/A
Commit fix:
N/A
Credit:
This bug was discovered by Agostino Sarubbo of Gentoo.
CVE:
CVE-2017-6845
Reproducer:
https://github.com/asarubbo/poc/blob/master/00172-podofo-nullptr-PoDoFo-PdfColor-operator
Timeline:
2017-02-13: bug discovered
2017-03-02: bug reported to upstream
2017-03-02: blog post about the issue
2017-03-12: CVE assigned
Note:
This bug was found with American Fuzzy Lop.
Permalink:
podofo: NULL pointer dereference in PoDoFo::PdfColor::operator= (PdfColor.cpp)