Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAHHvYcpseXiQc73gQqrb3Eumt05=8Chd9Nfv1qooVkMxON-RtQ@mail.gmail.com>
Date: Sat, 22 Apr 2017 11:02:21 +0800
From: Xiaobo Xiang <xiangxb2112@...il.com>
To: oss-security@...ts.openwall.com
Cc: cve-assign@...re.org
Subject: CVE Request: podofo: stack overflow in PoDoFo::PdfParser::ReadDocumentStructure(PdfParser.cpp
 )

Hi,

There is a infinite recursion in
PoDoFo::PdfParser::ReadDocumentStructure(PdfParser.cpp )
In the ReadDocumentStructure function, it calls ReadXRefContents several
time, for exmple in the end of ReadDocumentStructure:.
    try {
        ReadXRefContents( m_nXRefOffset );
    } catch( PdfError & e ) {
        e.AddToCallstack( __FILE__, __LINE__, "Unable to load xref
entries." );
        throw e;
    }

The ReadXRefContents and ReadXRefStreamContents will call each other if it
meet some conditions. Just as below.

void PdfParser::ReadXRefStreamContents( pdf_long lOffset, bool
bReadOnlyTrailer )
{
    m_device.Device()->Seek( lOffset );
    //....
    if(xrefObject.HasPrevious())
    {
        try {
            m_nIncrementalUpdates++;

            // PDFs that have been through multiple PDF tools may have a
mix of xref tables (ISO 32000-1 7.5.4)
            // and XRefStm streams (ISO 32000-1 7.5.8.1) and in the Prev
chain,
            // so call ReadXRefContents (which deals with both) instead of
ReadXRefStreamContents
            ReadXRefContents( xrefObject.GetPreviousOffset(),
bReadOnlyTrailer );
        } catch(PdfError &e) {
            //....
        }
    }
}

void PdfParser::ReadXRefContents( pdf_long lOffset, bool bPositionAtEnd )
{
    pdf_int64 nFirstObject = 0;
    pdf_int64 nNumObjects  = 0;

    if( !this->IsNextToken( "xref" ) )
    {
//      if( m_ePdfVersion < ePdfVersion_1_5 )
//        Ulrich Arnold 19.10.2009, found linearized 1.3-pdf's with
trailer-info in xref-stream
        if( m_ePdfVersion < ePdfVersion_1_3 )
        {
            PODOFO_RAISE_ERROR( ePdfError_NoXRef );
        }
        else
        {
            ReadXRefStreamContents( lOffset, bPositionAtEnd );
            return;
        }
    }

The crash log is just as follows:

./podofofuzzer: Running 1 inputs 1 time(s) each.
Running: crash-5aac275479284034b46368c836564266b0ed3694
ASAN:DEADLYSIGNAL
=================================================================
==30073==ERROR: AddressSanitizer: stack-overflow on address 0x7ffc70e74f18
(pc 0x0000004e6119 bp 0x7ffc70e75790 sp 0x7ffc70e74f20 T0)
    #0 0x4e6118  (/home/name/FUZZ-WORKSPACE/podofofuzzer+0x4e6118)
    #1 0x8a75c1  (/home/name/FUZZ-WORKSPACE/podofofuzzer+0x8a75c1)
    #2 0x4e6efc  (/home/name/FUZZ-WORKSPACE/podofofuzzer+0x4e6efc)
    #3 0x7fdbbe094277  (/usr/lib/x86_64-linux-gnu/libstdc++.so.6+0x121277)
    #4 0x61085e  (/home/name/FUZZ-WORKSPACE/podofofuzzer+0x61085e)

when debugging with gdb and checking the stack backtrace, it showed the
program runs out of the stack as below :

#6884 0x000000000063a434 in PoDoFo::PdfParser::ReadXRefStreamContents
(this=0x617000000080, lOffset=5923, bReadOnlyTrailer=false)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:875
#6885 0x000000000063438c in PoDoFo::PdfParser::ReadXRefContents
(this=0x617000000080, lOffset=5923, bPositionAtEnd=false) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:682
#6886 0x000000000063a434 in PoDoFo::PdfParser::ReadXRefStreamContents
(this=0x617000000080, lOffset=5923, bReadOnlyTrailer=false)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:875
#6887 0x000000000063438c in PoDoFo::PdfParser::ReadXRefContents
(this=0x617000000080, lOffset=5923, bPositionAtEnd=false) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:682
#6888 0x000000000063a434 in PoDoFo::PdfParser::ReadXRefStreamContents
(this=0x617000000080, lOffset=5923, bReadOnlyTrailer=false)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:875
#6889 0x000000000063438c in PoDoFo::PdfParser::ReadXRefContents
(this=0x617000000080, lOffset=5923, bPositionAtEnd=false) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:682
#6890 0x000000000063a434 in PoDoFo::PdfParser::ReadXRefStreamContents
(this=0x617000000080, lOffset=5923, bReadOnlyTrailer=false)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:875
#6891 0x000000000063438c in PoDoFo::PdfParser::ReadXRefContents
(this=0x617000000080, lOffset=5923, bPositionAtEnd=false) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:682
#6892 0x000000000063a434 in PoDoFo::PdfParser::ReadXRefStreamContents
(this=0x617000000080, lOffset=116, bReadOnlyTrailer=false)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:875
#6893 0x000000000063438c in PoDoFo::PdfParser::ReadXRefContents
(this=0x617000000080, lOffset=116, bPositionAtEnd=false) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:682
#6894 0x00000000006303bf in PoDoFo::PdfParser::ReadDocumentStructure
(this=0x617000000080) at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:337
#6895 0x000000000062e252 in PoDoFo::PdfParser::ParseFile
(this=0x617000000080, rDevice=..., bLoadOnDemand=true) at
/home/name/podofo-0.9.5/src/base/PdfParser.cpp:220
#6896 0x000000000062ce49 in PoDoFo::PdfParser::ParseFile
(this=0x617000000080, pszFilename=0x8ca380 <.str> "tempinput.pdf",
bLoadOnDemand=true)
    at /home/name/podofo-0.9.5/src/base/PdfParser.cpp:164
#6897 0x00000000005cdc65 in PoDoFo::PdfMemDocument::Load
(this=0x7fffffffbfe0, pszFilename=0x8ca380 <.str> "tempinput.pdf",
bForUpdate=false)
    at /home/name/podofo-0.9.5/src/doc/PdfMemDocument.cpp:256
#6898 0x00000000005cd682 in PoDoFo::PdfMemDocument::PdfMemDocument
(this=0x7fffffffbfe0, pszFilename=0x8ca380 <.str> "tempinput.pdf",
bForUpdate=false)
    at /home/name/podofo-0.9.5/src/doc/PdfMemDocument.cpp:102

Thus,causing denial of service.
​
 crash-5aac275479284034b46368c836564266b0ed3694
<https://drive.google.com/file/d/0B_D2GM9VAVyvanRadmhWd1RKM0U/view?usp=drive_web>
​

Best Regards,​​
Xiang Xiaobo

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.