-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =============================================================================== >> CERT-NL, 01-Mar-2000 << >> All CERT-NL information has been moved to http://cert.surfnet.nl. Links << >> to CERT-NL information contained in this advisory are therefore outdated. << >> << >> CERT-NL also has stopped the CERT-CC-Mirror service. Due to this the << >> links to the CERT-CC mirror are obsolete. Visit the CERT-CC site for the << >> complete CERT-CC advisory texts: http://www.cert.org << =============================================================================== =============================================================================== Security Advisory CERT-NL =============================================================================== Author/Source : CERT-NL Index : S-92-04 Distribution : SURFnet constituency Page : 1 Classification: External Version: final Subject : AT&T /usr/etc/rexecd Vulnerability Date : 25-feb-92 =============================================================================== CERT-NL (SURFnet Computer Emergency Response Team) has received information concerning a security problem in AT&T Unix software. CERT-NL wishes to thank CERT/CC for bringing this to our attention. =========================================================================== CA-92:04 CERT Advisory February 25, 1992 AT&T /usr/etc/rexecd Vulnerability - --------------------------------------------------------------------------- The Computer Emergency Response Team/Coordination Center (CERT/CC) has received information concerning a vulnerability in AT&T TCP/IP Release 4.0 running on SVR4 systems for both the 386/486 and 3B2 RISC platforms. The existing error, in the remote execution server /usr/etc/rexecd, has been corrected, and a new executable for rexecd is available from AT&T by calling 800-543-9935. Patches may be obtained outside the U.S. by calling your local technical support. The numbers associated with the fix are 5127 (3.5" media) and 5128 (5.25" media). The problem does not exist in TCP/IP release 3.2 for SVR3, or any earlier versions of the TCP/IP product running on either the 3B2 or 386 platforms. The version of TCP/IP distributed with SVR4 by UNIX(r) System Laboratories, Inc. (a subsidiary of AT&T) does not contain this vulnerability. UNIX(r) is a registered trademark of UNIX System Laboratories, Inc. - --------------------------------------------------------------------------- I. Description A vulnerability has been identified where root privileges may be accessed through the use of /usr/etc/rexecd. II. Impact A user on a remote machine may be able to run commands as root on the target host (the host running the affected /usr/etc/rexecd). III. Solution 1. Administrators of affected systems should execute, as root, the following command to immediately turn off access to rexecd until the new binary can be obtained. # chmod 400 /usr/etc/rexecd 2. Obtain and install the new patch. The fix will be supplied as one diskette, and it comes with one page of instructions documenting the procedure to replace the existing /usr/etc/rexecd binary. - --------------------------------------------------------------------------- The CERT/CC wishes to thank Bradley E. Smith, Network & Technical Services, Bradley University, for bringing this vulnerability to our attention and for providing a corresponding solution. We would also like to thank AT&T for their very quick response to this problem. - --------------------------------------------------------------------------- If you believe that your system has been compromised, contact CERT/CC or your representative in FIRST (Forum of Incident Response and Security Teams). Internet E-mail: cert@cert.sei.cmu.edu Telephone: 412-268-7090 (24-hour hotline) CERT/CC personnel answer 7:30 a.m.-6:00 p.m. EST(GMT-5)/EDT(GMT-4), on call for emergencies during other hours. Computer Emergency Response Team/Coordination Center (CERT/CC) Software Engineering Institute Carnegie Mellon University Pittsburgh, PA 15213-3890 Past advisories, information about FIRST representatives, and other information related to computer security are available for anonymous ftp from cert.sei.cmu.edu (192.88.209.5). ============================================================================== CERT-NL is the Computer Emergency Response Team for SURFnet customers. SURFnet is the Dutch network for educational, research and related institutes. CERT-NL is a member of the Forum of Incident Response and Security Teams (FIRST). All CERT-NL material is available under: http://cert.surfnet.nl/ In case of computer or network security problems please contact your local CERT/security-team or CERT-NL (if your institute is NOT a SURFnet customer please address the appropriate (local) CERT/security-team). CERT-NL is one/two hour(s) ahead of UTC (GMT) in winter/summer, i.e. UTC+0100 in winter and UTC+0200 in summer (DST). Email: cert-nl@surfnet.nl ATTENDED REGULARLY ALL DAYS Phone: +31 302 305 305 BUSINESS HOURS ONLY Fax: +31 302 305 329 BUSINESS HOURS ONLY Snailmail: SURFnet bv Attn. CERT-NL P.O. Box 19035 NL - 3501 DA UTRECHT The Netherlands NOODGEVALLEN: 06 22 92 35 64 ALTIJD BEREIKBAAR EMERGENCIES : +31 6 22 92 35 64 ATTENDED AT ALL TIMES CERT-NL'S EMERGENCY PHONENUMBER IS ONLY TO BE USED IN CASE OF EMERGENCIES: THE SURFNET HELPDESK OPERATING THE EMERGENCY NUMBER HAS A *FIXED* PROCEDURE FOR DEALING WITH YOUR ALERT AND WILL IN REGULAR CASES RELAY IT TO CERT-NL IN AN APPROPRIATE MANNER. CERT-NL WILL THEN CONTACT YOU. =============================================================================== -----BEGIN PGP SIGNATURE----- Version: PGP 6.5.1i iQA/AwUBOL6V9DSYjBqwfc9jEQJ7QwCgl2XpU3VKXNJSRCvurJ8odtgHAOkAoIfo bTZXiEK5zB5MGQDmaBf33Q7S =NyQB -----END PGP SIGNATURE-----