-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Local/Remote D.o.S Attack in InterAccess Telnet Server Release 4.0 *ALL BUILDS* for Windows95/98/WinNT Vulnerability USSR Advisory Code: USSR-2000034 Release Date: February 24 2000 Systems Affected: InterAccess TelnetD Server 4.0 for WinNT and others versions. InterAccess TelnetD Server 4.0 for Windows95/98 and others versions. InterAccess TelnetD Server 4.0 build 4 for WiNT InterAccess TelnetD Server 4.0 build 5 for WiNT InterAccess TelnetD Server 4.0 build 6 for WiNT InterAccess TelnetD Server 4.0 build 7 for WiNT (Release 4.0 Build Jan 5 2000) InterAccess TelnetD Server 4.0 for Windows95/98 Build 3 InterAccess TelnetD Server 4.0 for Windows95/98 Build (Release 4.0 Build Jan 6 2000) THE PROBLEM UssrLabs found a Local / Remote DOS Attack, The code that handles the Terminal client configurations to the Telnet server in the connection procedure, has an unchecked size that cause the TelnetD Service Crash. Binary or source for this D.O.S: http://www.ussrback.com/telnetd/dostelnetd.exe (binary) http://www.ussrback.com/telnetd/dostelnetd.zip (Source) Vendor Status: We show to the vendor the d.o.s Problem and the vendor think we pinging to the machine, so, that is like Vendor not contacted :) Vendor Url: http://www.pragmasys.com/ Program Url: http://www.pragmasys.com/TelnetD/ Program Url: http://www.pragmasys.com/Telnet95/ Credit: USSRLABS SOLUTION Contact Pragma Systems. NOTE: We try help pragma people to show their program is vulnerable to D.o.S attack, and the only responce of pragma was "STOP PING SERVER", so we decide release the advisory. Greetings: Eeye, Attrition, w00w00, beavuh, Rhino9, ADM, HNN, Technotronic and Wiretrip. u n d e r g r o u n d s e c u r i t y s y s t e m s r e s e a r c h http://www.ussrback.com -----BEGIN PGP SIGNATURE----- Version: PGPfreeware 6.5.2 for non-commercial use iQA/AwUBOLWkyNybEYfHhkiVEQKZGACeKRtpBWam+Hgplx9nRiWEy3yk4q8AoOHZ yo9eCjR9zbFHQOr5L1OBKvGs =cBLP -----END PGP SIGNATURE-----