-----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 to CERT-NL information contained in this advisory are therefore outdated.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-92-05 Distribution : SURFnet Constituency Page : 1 Classification: External Version: final Subject : AIX REXD Deamon Vulnerability Date : 05-mar-92 =============================================================================== CERT-NL (SURFnet Computer Emergency Response Team) has received information concerning a security problem in AIX REXD Deamon. CERT-NL wishes to thank CERT/CC for bringing this to our attention. =========================================================================== CA-92:05 CERT Advisory March 5, 1992 AIX REXD Daemon Vulnerability - --------------------------------------------------------------------------- The Computer Emergency Response Team/Coordination Center (CERT/CC) has received information concerning a vulnerability with the rexd daemon in versions 3.1 and 3.2 of AIX for IBM RS/6000 machines. IBM is aware of the problem and it will be fixed in future updates to AIX 3.1 and 3.2. Sites may call IBM Support (800-237-5511) and ask for the patch for apar ix21353. Patches may be obtained outside the U.S. by contacting your local IBM representative. The fix is also provided below. - --------------------------------------------------------------------------- I. Description In certain configurations, particularly if NFS is installed, the rexd (RPC remote program execution) daemon is enabled. Note: Installing NFS with the current versions of "mknfs" will re-enable rexd even if it was previously disabled. II. Impact If a system allows rexd connections, anyone on the Internet can gain access to the system as a user other than root. III. Solution CERT/CC and IBM recommend that sites take the following actions immediately. These steps should also be taken whenever "mknfs" is run. 1. Be sure the rexd line in /etc/inetd.conf is commented out by having a '#' at the beginning of the line: #rexd sunrpc_tcp tcp wait root /usr/etc/rpc.rexd rexd 100017 1 2. Refresh inetd by running the following command as root: refresh -s inetd - --------------------------------------------------------------------------- The CERT/CC wishes to thank Darren Reed of the Australian National University for bringing this vulnerability to our attention and IBM for their response to the 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/AwUBOL6V9DSYjBqwfc9jEQLXrwCg2uk09QlBvjDecXoWjsWlYr0E+C4AniDG OK8lJ5eNLtrfKlec6fzWIEaJ =8wLa -----END PGP SIGNATURE-----