podofo: NULL pointer dereference in PoDoFo::PdfParser::ReadXRefSubsection (PdfParser.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’m unable to communicate with them.

The complete ASan output:

# podofopdfinfo $FILE
==9418==ERROR: AddressSanitizer: SEGV on unknown address 0x0000000000d8 (pc 0x7f496cb0ab76 bp 0x7ffff028f9d0 sp 0x7ffff028f148 T0)                                                                                                                                             
==9418==The signal is caused by a WRITE memory access.                                                                                                                                                                                                                         
==9418==Hint: address points to the zero page.                                                                                                                                                                                                                                 
    #0 0x7f496cb0ab75  /var/tmp/portage/sys-libs/glibc-2.22-r4/work/glibc-2.22/string/../sysdeps/x86_64/multiarch/memcpy-ssse3-back.S:1989                                                                                                                                     
    #1 0x4c063e 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                                                                                                                               
    #2 0x7f496dde143c in void std::_Construct(PoDoFo::PdfParser::TXRefEntry*, PoDoFo::PdfParser::TXRefEntry const&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_construct.h:83:38             
    #3 0x7f496dde143c in void std::__uninitialized_fill_n::__uninit_fill_n(PoDoFo::PdfParser::TXRefEntry*, unsigned long, PoDoFo::PdfParser::TXRefEntry const&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_uninitialized.h:202                                                                                                                                                                                                                       
    #4 0x7f496dde143c in void std::uninitialized_fill_n(PoDoFo::PdfParser::TXRefEntry*, unsigned long, PoDoFo::PdfParser::TXRefEntry const&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_uninitialized.h:244                                                                                                                                                                                                                                                 
    #5 0x7f496dde143c in void std::__uninitialized_fill_n_a(PoDoFo::PdfParser::TXRefEntry*, unsigned long, PoDoFo::PdfParser::TXRefEntry const&, std::allocator&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_uninitialized.h:355                                                                                                                                                              
    #6 0x7f496dde143c in std::vector<PoDoFo::PdfParser::TXRefEntry, std::allocator >::_M_fill_insert(__gnu_cxx::__normal_iterator<PoDoFo::PdfParser::TXRefEntry*, std::vector<PoDoFo::PdfParser::TXRefEntry, std::allocator > >, unsigned long, PoDoFo::PdfParser::TXRefEntry const&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/vector.tcc:496                                                                                                                                 
    #7 0x7f496ddd4a67 in std::vector<PoDoFo::PdfParser::TXRefEntry, std::allocator >::insert(__gnu_cxx::__normal_iterator<PoDoFo::PdfParser::TXRefEntry*, std::vector<PoDoFo::PdfParser::TXRefEntry, std::allocator > >, unsigned long, PoDoFo::PdfParser::TXRefEntry const&) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_vector.h:1073:9                                                                                                                                    
    #8 0x7f496ddd4a67 in std::vector<PoDoFo::PdfParser::TXRefEntry, std::allocator >::resize(unsigned long, PoDoFo::PdfParser::TXRefEntry) /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.3/include/g++-v4/bits/stl_vector.h:716                          
    #9 0x7f496ddd4a67 in PoDoFo::PdfParser::ReadXRefSubsection(long&, long&) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfParser.cpp:772                                                                                                                   
    #10 0x7f496ddc60bd in PoDoFo::PdfParser::ReadXRefContents(long, bool) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfParser.cpp:725:17                                                                                                                   
    #11 0x7f496ddbfaae in PoDoFo::PdfParser::ReadDocumentStructure() /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfParser.cpp:337:9                                                                                                                         
    #12 0x7f496ddbce1f in PoDoFo::PdfParser::ParseFile(PoDoFo::PdfRefCountedInputDevice const&, bool) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfParser.cpp:220:9                                                                                        
    #13 0x7f496ddbb1e4 in PoDoFo::PdfParser::ParseFile(char const*, bool) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/base/PdfParser.cpp:164:11                                                                                                                   
    #14 0x7f496e018393 in PoDoFo::PdfMemDocument::Load(char const*) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/doc/PdfMemDocument.cpp:186:16                                                                                                                     
    #15 0x7f496e018062 in PoDoFo::PdfMemDocument::PdfMemDocument(char const*) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/src/doc/PdfMemDocument.cpp:88:11                                                                                                            
    #16 0x511b44 in PdfInfo::PdfInfo(std::string const&) /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofopdfinfo/pdfinfo.cpp:25:16                                                                                                                            
    #17 0x521ac8 in main /tmp/portage/app-text/podofo-0.9.4/work/podofo-0.9.4/tools/podofopdfinfo/podofopdfinfo.cpp:110:15                                                                                                                                                     
    #18 0x7f496c9f461f in __libc_start_main /var/tmp/portage/sys-libs/glibc-2.22-r4/work/glibc-2.22/csu/libc-start.c:289                                                                                                                                                       
    #19 0x41e8f8 in _start (/usr/bin/podofopdfinfo+0x41e8f8)                                                                                                                                                                                                                   
                                                                                                                                                                                                                                                                               
AddressSanitizer can not provide additional info.                                                                                                                                                                                                                              
SUMMARY: AddressSanitizer: SEGV /var/tmp/portage/sys-libs/glibc-2.22-r4/work/glibc-2.22/string/../sysdeps/x86_64/multiarch/memcpy-ssse3-back.S:1989                                                                                                                            
==9418==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-2017-5855

Reproducer:
https://github.com/asarubbo/poc/blob/master/00134-podofo-nullptr-pdfparser-cpp

Timeline:
2017-01-05: bug discovered
2017-02-01: blog post about the issue
2017-02-02: CVE assigned

Note:
This bug was found with American Fuzzy Lop.

Permalink:
https://blogs.gentoo.org/ago/2017/02/01/podofo-null-pointer-dereference-in-podofopdfparserreadxrefsubsection-pdfparser-cpp

This entry was posted in advisories, security. Bookmark the permalink.

One Response to podofo: NULL pointer dereference in PoDoFo::PdfParser::ReadXRefSubsection (PdfParser.cpp)

  1. Pingback: SB17-065: Vulnerability Summary for the Week of February 27, 2017 – sec.uno

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.