Secunia Research has discovered some vulnerabilities in Xpdf, which can e exploited by malicious people to compromise a user's system. 1) An array indexing error within the DCTStream::readProgressiveDataUnit()" method in xpdf/Stream.cc can be xploited to corrupt memory via a specially crafted PDF file. 2) An integer overflow error within the "DCTStream::reset()" method in pdf/Stream.cc can be exploited to cause a heap-based buffer overflow via a specially crafted PDF file. 3) A boundary error within the "CCITTFaxStream::lookChar()" method in xpdf/Stream.cc can be exploited to cause a heap-based buffer overflow by tricking a user into opening a PDF file containing a specially crafted "CCITTFaxDecode" filter. Successful exploitation may allow execution of arbitrary code.