1. OVERVIEW The Nuance PDF Reader application is vulnerable to Insecure DLL Hijacking Vulnerability. Similar terms that describe this vulnerability have been come up with Remote Binary Planting, and Insecure DLL Loading/Injection/Hijacking/Preloading.
2. PRODUCT DESCRIPTION The free Nuance PDF Reader is an alternative to Adobe Reader that is smaller, more secure, and for the first time connects desktop PDF with cloud-based PDF-to-Microsoft Office conversion services. The Nuance PDF Reader also enables PDF form save, annotations and Microsoft SharePoint features not available in alternatives. 3. VULNERABILITY DESCRIPTION The Nuance PDF Reader application passes an insufficiently qualified path in loading its external libraries - "dwmapi.dll, exceptiondumpdll.dll" when a user opens its associated file with extension - pdf . 4. VERSIONS AFFECTED 6.0 and probably lower versions 5. PROOF-OF-CONCEPT/EXPLOIT http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/nuance_pdf_reader/poc/movie/nuance_pdf_reader-6.0_dll-hijacking.mp4 http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/nuance_pdf_reader/poc/nuance_pdf_reader-6.0_dll-hijacking-poc.zip Tested Platform: Windows XP Service Pack 3 (Fresh Windows) 6. IMPACT Attackers can trigger a successful exploit against a victim user in a number of ways such as placing a malicious external library file made as hidden attribute and a seemingly interesting file in network shares, usb drives, file sharing networks, social networks, ..etc 7. SOLUTION Fixed version from the vendor has not been released yet. However, it is suggested that the following workarounds be deployed by users to protect increasing mass exploitation of this vulnerability class: - Disable loading of libraries from WebDAV and remote network shares - Disable the WebClient service Please see workaround solution links in References section. 8. VENDOR Nuance Communications http://www.nuance.com/ 9. CREDIT This vulnerability was discovered by Aung Khant, http://yehg.net, YGN Ethical Hacker Group, Myanmar. 10. DISCLOSURE TIME-LINE 09-07-2010: notified vendor 09-13-2010: vulnerability disclosed 11. REFERENCES Original Advisory URL: http://core.yehg.net/lab/pr0js/advisories/dll_hijacking/[nuance_pdf_reader]_6.0_insecure_dll_hijacking Workaround Solution: http://support.microsoft.com/kb/2264107 Workaround Solution: https://www.microsoft.com/technet/security/advisory/2269637.mspx#EGF Developer Solution: http://msdn.microsoft.com/en-us/library/ff919712%28v=VS.85%29.aspx Unofficial DLL Hijacking List: http://www.corelan.be:8800/index.php/2010/08/25/dll-hijacking-kb-2269637-the-unofficial-list/ Testing for DLL Hijacking: http://core.yehg.net/lab/pr0js/view.php/when_testing_for_dll_hijacking.txt #yehg [09-13-2010] _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
