Subject: eSecurityOnline Security Advisory 2408 - CIDER SHADOW CGI - msg#00408

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Re: CORE-20020409: Multiple vulnerabilities in stack smashing protection technologies

On Tue, 23 Apr 2002, [iso-8859-1] Iván Arce wrote: > 1) Control of function's arguments > > In [8] and [9] a method to exploit stack based buffer overflows on stack > protected > programs is presented. In the example, a local pointer is used to write to > arbitrary > memory locations within the program's memory space. This technique can be > extended > to exploit the fact that in standard C compiled programs, function arguments > are located > in the stack at "higher" addresses than the return address: > Above technique (extended) WAS described in [8] (http://www.phrack.org/show.php?p=56&a=5): "In this example we have our pointer (dst) on the stack beyond the canary and RET value, so we cannot change it without killing the canary and without being caught... Or can we? Both StackGuard and StackShield check whether RET was altered before the function returns to its caller (this done at the very end of function). In most cases we have enough time here to do something to take control of a vulnerable program. We can do it by overwriting the GOT entry of the next library function called. We don't have to worry about the order of local variables and since we don't care if canary is alive or not, we can play!" > 2) Returning with an altered frame pointer It WAS described in [8] also: "StackShield protection can be bypassed by overwriting the saved %ebp which is not protected. One way of exploiting it (under the worst conditions) was described in >>The Frame Pointer Overwrite<< by klog in Phrack 55 [4]." "[4] klog. The Frame Pointer Overwrite http://www.phrack.com/search.phtml?view&article=p55-8" > 4) Pointing the caller's frame to the Global Offset Table (GOT) VERY interestin aproach! :) All I wanted to say is that most of above was described (clearly? ;) in the fall of 1999 and published in May 2000. Anyway: THX for credits. -- Mariusz Wołoszyn Internet Security Specialist, Internet Partners

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eSecurityOnline Security Advisory 2397 - Sun Solaris admintool -d and PRODVERS buffer overflow vulnerabilities

eSO Security Advisory: 2397 Discovery Date: March 28, 2000 ID: eSO:2397 Title: Sun Solaris admintool -d and PRODVERS buffer overflow vulnerabilities Impact: Local attackers can gain root privileges Affected Technology: Solaris 2.5, 2.5.1, 2.6, 7, 8 SPARC and x86 Vendor Status: Patches are available Discovered By: Kevin Kotas of the eSecurityOnline Research and Development Team CVE Reference: CAN-2002-0089 Advisory Location: http://www.eSecurityOnline.com/advisories/eSO2397.asp Description: The Sun Solaris admintool utility is vulnerable to multiple buffer overflow conditions that allow a local attacker to gain root access. The problems are due to insufficient bounds checking on command line options and on a configuration file variable. An attacker can use a carefully constructed string with the -d command line option or with the PRODVERS .cdtoc file variable to gain root privileges. The first buffer overflow is related to command line execution of admintool with the -d switch, when a long string is used with "/Solaris" present. The second buffer overflow occurs due to a lack of bounds checking for the PRODVERS argument in the .cdtoc file. The .cdtoc file is used to specify variables for installation media. Through the software/edit/add feature, a local directory can be specified that contains a .cdtoc file. The file can contain a string of data for the PRODVERS variable that will cause the program to crash or execute code when processed. Technical Recommendation: Apply the following patches. Solaris 2.5: 103247-16 Solaris 2.5_x86: 103245-16 Solaris 2.5.1: 103558-16 Solaris 2.5.1_x86: 103559-16 Solaris 2.6: 105800-07 Solaris 2.6_x86: 105801-07 Solaris 7: 108721-02 Solaris 7_x86: 108722-02 Solaris 8: 10453-01 Solaris 8_x86: 110454-01 As a workaround solution, remove the setuid permissions with the following: chmod -s /usr/bin/admintool Vendor site: http://sunsolve.sun.com Acknowledgements: eSecurityOnline would like to thank Sun Microsystems and the Sun security team for their cooperation in resolving the issue. Copyright 2002 eSecurityOnline LLC. All rights reserved. THE INFORMATION IN THIS VULNERABILITY ALERT IS PROVIDED BY ESECURITYONLINE LLC "AS IS", "WHERE IS", WITH NO WARRANTY OF ANY KIND, AND ESECURITYONLINE LLC HEREBY DISCLAIMS THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ESECURITYONLINE LLC SHALL HAVE NO LIABILITY FOR ANY DAMAGE, CLAIM OR LOSS RESULTING FROM YOUR USE OF THE INFORMATION CONTAINED IN THIS VULNERABILITY ALERT.

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ITCP Advisory 13: Bypassing of ATGuard Firewall possible

- ------------------------------------------------------------ itcp advisory 13 advisories@xxxxxxxxxxxxxxxxx http://www.it-checkpoint.net/advisory/12.html April 29th, 2002 - ------------------------------------------------------------ ITCP Advisory 13: Bypassing of ATGuard Firewall possible - ------------------------- Affected programs: ATGuard Personal Firewall (At least Version 3.2, probably others) URL: Not existant any more, the software is still wide spread Vendor: The ATGuard-Technology was bought by Norton and included in it's Norton Personal Firewall Vulnerability-Class: Bypassing of a personal Firewall (Desktop Firewall) OS specific: Windows Problem-Type: local and remote SUMMARY ATGuard is a very good personal desktop firewall, which comes with a wide range of possibilities: - Firewall functions - Webfilter functions - Privacy protection functions It is also possible, to allow specific connections bound to applications (for example, you can allow all connections to Port 80 on any host for Internet Explorer). Futher, it is possible to protect the firewall configuration (and start & stop of it) with a password. This could be a great possibility, to control the activities of children and youths in the internet. DETAILS As mentioned before, it is possible to allow for specific applications specific connections. For example, most users use Internet Explorer to browse the internet. It is a logical assumption, that people using the Internet Explorer to browse the WWW allow outbound connections to all hosts at least to the destination port 80. Sadly ATGuard doesn't save the file paths / doesn't use checksums (would be much better), to determine wether the executed program is real the one, that is allowed to connect to all hosts on port 80. It just uses the filename (in this case "IEXPLORE.EXE"). IMPACT ATGuard can be fooled to think that a disallowed program is allowed to connect to the internet. Trojan horses which use outbound connections or using HTTP-Tunneling-Software to tunnel unwanted connections (like ICQ) are not blocked. EXPLOIT There are many different possibilities to exploit this. This is a sample how to get ICQ working on a computer, on which only Internet Explorer is allowed to connect to port 80. All other outbound connections are blocked by ATGuard. Download the HTTP-Tunnel-Client from www.HTTP-Tunnel.com. Install it to your computer. When you try to configure it, it will tell you, that it can't find the HTTP-Tunnel-Server. Now, just rename / copy the File "HTTP-Tunnel Client.exe" to "IEXPLORE.EXE". Fire it up again using the IEXPLORE.EXE-Filename. After short time it should tell you, that it is working correctly. As said before, it is possible to use trojan horses to fool bad configured firewalls, etc... SOLUTION There doesn't exist an solution, since ATGuard is not developped anymore. We were not able to test the Norton Personal Firewall for this problem, since no one of us owns it. We are contacting Norton directly with this Advisory. ADDITIONAL INFORMATION Vendor has not been contacted. (since he doesn't exist anymore). Since there exist more personal firewalls like ATGuard, we will have a look at the free ones and try the same. Bugs discovered and published by Florian "BlueScreen" Hobelsberger BlueScreen@xxxxxxxxxxxxxxxxx ) from www.IT-Checkpoint.net ----------------------- DISCLAIMER: The information in this bulletin is provided "AS IS" without warranty of any kind. In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages.

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eSecurityOnline Security Advisory 2397 - Sun Solaris admintool -d and PRODVERS buffer overflow vulnerabilities

eSO Security Advisory: 2397 Discovery Date: March 28, 2000 ID: eSO:2397 Title: Sun Solaris admintool -d and PRODVERS buffer overflow vulnerabilities Impact: Local attackers can gain root privileges Affected Technology: Solaris 2.5, 2.5.1, 2.6, 7, 8 SPARC and x86 Vendor Status: Patches are available Discovered By: Kevin Kotas of the eSecurityOnline Research and Development Team CVE Reference: CAN-2002-0089 Advisory Location: http://www.eSecurityOnline.com/advisories/eSO2397.asp Description: The Sun Solaris admintool utility is vulnerable to multiple buffer overflow conditions that allow a local attacker to gain root access. The problems are due to insufficient bounds checking on command line options and on a configuration file variable. An attacker can use a carefully constructed string with the -d command line option or with the PRODVERS .cdtoc file variable to gain root privileges. The first buffer overflow is related to command line execution of admintool with the -d switch, when a long string is used with "/Solaris" present. The second buffer overflow occurs due to a lack of bounds checking for the PRODVERS argument in the .cdtoc file. The .cdtoc file is used to specify variables for installation media. Through the software/edit/add feature, a local directory can be specified that contains a .cdtoc file. The file can contain a string of data for the PRODVERS variable that will cause the program to crash or execute code when processed. Technical Recommendation: Apply the following patches. Solaris 2.5: 103247-16 Solaris 2.5_x86: 103245-16 Solaris 2.5.1: 103558-16 Solaris 2.5.1_x86: 103559-16 Solaris 2.6: 105800-07 Solaris 2.6_x86: 105801-07 Solaris 7: 108721-02 Solaris 7_x86: 108722-02 Solaris 8: 10453-01 Solaris 8_x86: 110454-01 As a workaround solution, remove the setuid permissions with the following: chmod -s /usr/bin/admintool Vendor site: http://sunsolve.sun.com Acknowledgements: eSecurityOnline would like to thank Sun Microsystems and the Sun security team for their cooperation in resolving the issue. Copyright 2002 eSecurityOnline LLC. All rights reserved. THE INFORMATION IN THIS VULNERABILITY ALERT IS PROVIDED BY ESECURITYONLINE LLC "AS IS", "WHERE IS", WITH NO WARRANTY OF ANY KIND, AND ESECURITYONLINE LLC HEREBY DISCLAIMS THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ESECURITYONLINE LLC SHALL HAVE NO LIABILITY FOR ANY DAMAGE, CLAIM OR LOSS RESULTING FROM YOUR USE OF THE INFORMATION CONTAINED IN THIS VULNERABILITY ALERT.