************************************************************************** Security Bulletin 9616 DISA Defense Communications System August 21, 1996 Published by: DISN Security Coordination Center (SCC@NIC.DDN.MIL) 1-(800) 365-3642 DEFENSE INFORMATION SYSTEM NETWORK SECURITY BULLETIN The DISN SECURITY BULLETIN is distributed by the DISN SCC (Security Coordination Center) under DISA contract as a means of communicating information on network and host security exposures, fixes, and concerns to security and management personnel at DISN facilities. Back issues may be obtained via FTP (or Kermit) from NIC.DDN.MIL [192.112.36.5] using login="anonymous" and password="guest". The bulletin pathname is scc/sec-yynn (where "yy" is the year the bulletin is issued and "nn" is a bulletin number, e.g. scc/sec-9544.txt). These are also available at our WWW site, http://nic.ddn.mil. ************************************************************************** + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + ! ! ! The following important advisory was issued by the Automated ! ! Systems Security Incident Support Team (ASSIST) and is being ! ! relayed unedited via the Defense Information Systems Agency's ! ! Security Coordination Center distribution system as a means ! ! of providing DISN subscribers with useful security information. ! ! ! + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + -----BEGIN PGP SIGNED MESSAGE----- ASSIST's www site http://www.assist.mil <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Automated Systems Security Incident Support Team _____ ___ ___ _____ ___ _____ | / /\ / \ / \ | / \ | | / Integritas / \ \___ \___ | \___ | | < et /____\ \ \ | \ | | \ Celeritas / \ \___/ \___/ __|__ \___/ | |_____\ <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Bulletin 96-14 Release date: 20 August ,1996, 11:30 EDT (GMT -4) SUBJECT: Vulnerability in Solaris vold - - ----------------------------------------------------------------------------- SUMMARY: There is a report of a vulnerability in the Sun Microsystems Solaris 2.x distribution involving the Volume Management daemon, vold(1M). This program is used to help manage CDROM and floppy devices. IMPACT: This vulnerability may allow a local user to gain root privileges. Exploit details involving this vulnerability have been made publicly available. RECOMMENDED SOLUTIONS: Sites should take the actions suggested in Section 3 until official patches are available. - - ----------------------------------------------------------------------------- 1. Description The Volume Management daemon, vold(1M), manages the CDROM and floppy devices. For example, it provides the ability to automatically detect, and then mount, removable media such as CDROMs and floppy devices. vold is part of the Solaris 2.x Volume Management package (SUNWvolu). It is executed as a background daemon on system startup and runs as root. When vold detects that a CDROM or floppy has been inserted into a drive, it is configured to automatically mount the media, making it available to users. Part of this process includes the creation of temporary files, which are used to allow the Openwindows File Manager, filemgr(1), to determine that new media has been mounted. These files are created by the action_filemgr.so shared object which is called indirectly by vold through rmmount(1M). The handling of these files is not performed in a secure manner. As vold is configured to access these temporary files with root privileges, it may be possible to manipulate vold into creating or over-writing arbitrary files on the system. This vulnerability requires that vold be running and media managed by vold, such as a CDROM or floppy, be physically loaded into a drive. Note that a local user need not have physical access to the media drive to exploit this vulnerability. It is enough to wait until somebody else loads the drive, exploiting the vulnerability at that time. This vulnerability is known to be present in Solaris 2.4 and Solaris 2.5. Solaris distributions prior to Solaris 2.4 are also expected to be vulnerable. 2. Impact Local users may be able to create or over-write arbitrary files on the system. This can be leveraged to gain root privileges. 3. Workaround It is believed that the workarounds given in Sections 3.1 or 3.2 will address this vulnerability. Vendor patches may also address this vulnerability in the future (Section 3.3). 3.1 Edit /etc/rmmount.conf The temporary files which are susceptible to attack are created by the /usr/lib/rmmount/action_filemgr.so.1 shared object which is called indirectly by vold through rmmount(1M). rmmount(1M) can be configured so that it does not create the temporary files, thereby removing this vulnerability. To our knowledge, configuring rmmount(1M) in this fashion will not affect the functionality of vold. It will, however, remove the ability of the Openwindows File Manager, filemgr(1), to automatically detect newly mounted media. To prevent rmmount(1M) creating temporary files, sites must edit the /etc/rmmount.conf file and comment out (or remove) any entry which references action_filemgr.so. The standard /etc/rmmount.conf contains the following entries which must be commented out (or deleted) to remove this vulnerability: action cdrom action_filemgr.so action floppy action_filemgr.so After applying this workaround, an example of /etc/rmmount.conf may look like: # @(#)rmmount.conf 1.2 92/09/23 SMI # # Removable Media Mounter configuration file. # # File system identification ident hsfs ident_hsfs.so cdrom ident ufs ident_ufs.so cdrom floppy pcmem ident pcfs ident_pcfs.so floppy pcmem # Actions # # Following two lines commented out to remove vold vulnerability # # action cdrom action_filemgr.so # action floppy action_filemgr.so Note that vold does not have to be restarted for these changes to take effect. 3.2 Remove the Volume Management system Sites who do not require the vold functionality should remove the complete set of Volume Management packages. These are SUNWvolg, SUNWvolu and SUNWvolr. These packages can be removed using pkgrm(1M). 3.3 Install vendor patches Currently, we are not aware of any official patches which address this vulnerability. When official patches are made available, we suggests that they be installed. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ASSIST wishes to thanks AUSCERT, Leif Hedstrom, Mark McPherson(QTAC), Marek Krawus(UQ), DFN-CERT and CERT/CC for their assistance in this matter. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> - -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6 mQCNAi4uZ40AAAEEAM1uraimCNeh5PtzX7KoGxC2u8uMTdl8V5sujk3MHbWvCuOM W0FqDy5s9iwfQLZWzJ7cbM6L0mNOj8eJGoz7TqGKZDDRFlKAwg0x8joleZLC2gXw FVdF/g6Mdv7ok7heoa+Y//YMeADnsSrmzqLCnhFbKYffww3EbdH6sbnW3Io9AAUR tB9BU1NJU1QgVGVhbSA8YXNzaXN0QGFzc2lzdC5taWw+iQCVAwUQMJVF1JtBJ/Qs yeedAQFnqgQAp1rw7ONT41Mr3gHGs2aVpEwgOH6SeJ9sHZxUp4dJu+ogRMFrqdC+ +NBfzitzj9m1udFVDHpwsGawbv6wg43DDAKaTgIETCHYXa/OM5/9FCS3xJwC99Gb V1iOm8S/Q9FcJruKID9DG2WUJp2yPj+CjTuBQeLjGkqGjuSOR1TNXQiJAJUDBRAw lUPuYKf6jFkmJQkBAWg5A/9ykgo2ULWUsSzZjRkO9yPZUPAlpfH7ReaHwkapK69F fBzqwwQ8Gig1mL+qgmOHS8Zv+OAT491sWWsECN+dfpopFdsgS4Sec19ZjcMyhL1c BVIS9Cmbjetb6Kvfc39AMr0MRCrUlOkUd4qScjHysHFYRAwCl3STRjprNnUPKQbn f4kAlQMFEDB482bk8movIjSrbQEB/VgD/iap/CAb1jq8wMA3QleU8d6/QUqoPzgp jRhP0wP7K2GLVUV0d5sP4EptmzejqViZvlzt6ufnI1bML0Yt2U5loAeblnh714RX JcOmyAah6niiJSKuhCsYUzW6f3EBzXBn5tcu3GP35h+1VQunCQCMICCfnZ0r8Wcv EdwE9LxPYdueiQCVAwUQMHOjMwJPhGsUbeKNAQGOagQAgT5p6CwrIPpi+12yJ170 ekc3MPp8z0aNbvdCQWXTK6qtq1LmS65VeH0RE5xRponsgbWp+5JBvD22v0eGuSg7 7bnHT1HPXazPERAp8sw1zTERs7drMQE+JhHYylh3orKzHNf5EjFx10vwEXdfvGSc sP3Vpcx2xu0lUYHp5oHtPFiJAJUDBRAwar4DFKHh5Qavqe0BAeQqA/4xd0tdq9yF eUYrd1+ZriayzfSjCcIUlCDH1i7vXw1kiHkg2YpOoZLD9k+zNkbOyBs/r570fGHu A23SvUcUfaBUijT1jf9YGU5MQMdpx3p5qqI4kJ0GWUNySZNtaFy0qWNH8Z8NsNp3 FWllVeisye0qe96aoizW0dAyUymlM6YYn4kAlQMFEDBqqvga2zTcAviMgQEBN8wE AIu7O/Of4c1OvMc5tti4+gcyCVw41+fLjxQFB5EtkoW8Js6XhCsv3GcmzgCZw3g8 Sux7wxGe+lspZNV9rvv+JkDBWkA9O5HyOdmdv5JZM1UH41NettZM9Yw7kUtO7lAT aOb4ybHlqrBwJ8/+Lig7r7PwTL847JyGa3g229pGG/uEiQCVAwUQMGpTK+glSuMP TJd1AQE8KQP8Cu+FYuagNoBRllMIQryT9+0ngLRxJJTcTgIbLX4OPwa27JuXCukG kUIXRWFCqkRqkM/7ImZXeuUL4PmAX07f9ygGH7BUyqefhIWkxWFDaGHJVlg3l/pS Wh7NnC+nU6DUJNSzfwYStCABNptOcMiYaT1fY0+DkWpIgJVRTptquOWJAJUCBRAw aHX+IlGW2WZtAFEBATkXA/40QTxVP/x3aJDgC11cvFhwT7M+qJvhGSTRJOtrFz8i soZzihMeaQ8zLiu73dDlFz2E4f0+ettxsDcgFJADNmZ5H7WkPlf9gBUBne4KP2Y6 yIjOCMwd6T7HGm/ErF88DIJ2wn8irhzVRnBBWhnmQfSzr5a7mkjlA6GzAlFucGp3 eokAlQMFEDBpzIC58yc3bMt0GQEBgd4EAI0mE/5wXSWuBNApkALLjPAchBdeC4Kl YF4hQkfY/4YddeIasgTmINKOc5gJWgTHxPI2xKxjTAQhIZlOxuDyXWnBuK+x2hr4 iCh5unEIH+qaqdipGwWjFq0IZEmOOJaBRxlVt2hrmY6nRMpekitFLw8dhWHgI968 WVhJpWfBg+MhiQCVAwUQMGnMcmJl+kgHVnRVAQF+nQP/XK4xmIx1SmjoN9D+vNRY PSiKz8KEzh1Y2/5QTYA7iES8QXC4i/8HOWK7lyoL6FmWGxKYpU8isQ+DJpk0A4N0 U04JexpyFa0EeM/wsfp0YvAWesSVhV5UkDQU6hSC0U8rS1j/qtnSLZ4wXpapPSBh 82daDlxAQCVMzDoQYQZkMi+JAJUDBRAwacftBCZ9eY4KSdEBAbKGA/0VHArALL6v d0a0x7sn4o60Bk2fFzuaCBNTNzb11OOtuu47KMOZLwrl2jv+32ysIVEOXx+puhXP nQAgRrH0LGKV5FOY3B98AHuV+woOmfVjM2T3xB4Bs52Dz+HIIIhaWzzy3955tlp/ 6UyvZnD0QFLS/bre/Pog1Lgl0pxonmILhYkAlQIFEDBpJpXAx/wW8A8EIQEBPVoD /jwgG+7ZrWrb8/dqe6IZhSk8rq0JIHhSA2Hz1T7PhRvyDiquBJ3ulTeaX3BvuWqF bMuLJ4CTqXw9dexDehEnhGlxYycSXVzy8a34pLnmldii8oNvI1bLWMgd4HdM/PPZ GOgHmSIGrXMChkbddt9AoszDI0Whlbe9+wn6AeZVrJVaiQCVAgUQMGkkL2yh0IcG ee2RAQHrTgQAvBRce0S9yBvI/ufC/1jhE3LuUoA3YDdA8+UQ+UekaslZzOEgPs4K Za/nM9Y2vaRYscyzyIg8FGTzCdJQ2be9HZjSkB2xQuakeq88tlV32/cLcQSC8Zrw xsnPWujbIcWYg7B0hv8cCovef/w4kC9GyhjhIzPIsQ/Cr7/TYzheK12JAJUDBRAw Z/38o2xF3nu86kkBARanA/0XO4HBo6pT2xNCdQ7AW9UrvmTCiYUb0XVY7qCnkaPp Sn1KjsK2nGueDMGUBzvx9zWZ0xHAS+BSNkoM61gb9455KcbDwRqw6+47O/WuX1w9 fh7egjTY0kqN6YsP/vtirOuP+Krh19w/s6cDxbEBNbJIiZofRDFRRsZcZ8E2mLCP UIkAlQMFEDBn/EY7f8e8znZrHwEBxQwD/jP+CiwO3Nk45M5Ei++TZzdp7ak82hum XxVXplV2G4w8DN86pfl3IV/XvU67FQXg4NKJr+wm3JknDtlKZTE5g+aKkOYK6Fqt w3FjTd6PTDz11YRruCsdvBeYwMcHPe5XzIhgkwkMXX2Mp99q9LGKfV3087do2LNr V/2S/atn6IuqiQCVAwUQMGW6OliXq3zaXLJBAQFLwgP/bQ1C/Ph54RlRqw9rovJo SXp5wvQAfVqqnkL5nIIIK2uGputcmhMP8RqYKuRv4xaezkCDTeIE/P0327Ajc4// ca4SZCojxfqtrhw3EkfZtvFLJh1tsvAkqZkgHmjJxwA+lY78lQ1ncBZ99dePpuHu MBQew3769SkEA8kk/s5XiYqJAJUDBRAvXHHu0fqxudbcij0BAQFjA/0W8glucqO0 wtSPyCF3qGimFLHxZmd9Cw6Zlf8Ftfy8rPVrkGQGfioA29b64oZ1SUTwsswSbU8P n0KKFxvc6hYM5TzMg4gSu+vLh6pr4vMRdXyecF16z4BrUwIwZLP4rc5o/vyVDskI ahj1NdNYh6V8B0FUEbhVBxJBGfy2NF0bZ7QoQVNTSVNUIFRlYW0gPGFzc2lzdEBh c3Npc3QuaW1zLmRpc2EubWlsPokAlQIFEC45Ys3KbyuD/AwC1QEBKPED/2dwnN+/ OE2iHhvGwv3jZtsm6cH+GVkpNpc0w0vQOKvVwUnLwuETSv+eryz9Fl7nL0U2tv/5 V81dXqqc5C7EvOQW1Dt9RBSjEOundYrOzsfELIMrwh1iJXsIxG7g7iil0HeKzxsQ E/nBFwJbgP6SQaYF4wy7TPuXw+IVVddp0p1riQCVAgUQLi5x6IdGPdIwvm+pAQFN EwP+Ml0i+yurXH1ZvQApz+HKwqLrRTNsNdHu2CsQ/OdGo4Vq4eqyPTvrI1OVjm6o jye7GR3RMPygEcz0oox/+YfB5cmGugpZLFsWLspswrFGGCXLXY3Bq7mpH14GENU5 JMlHzazeRvdDbkSv700Xu25JshjWIzfTY2nNUNfFlRefQoY= =8gi/ - -----END PGP PUBLIC KEY BLOCK----- ASSIST is an element of the Defense Information Systems Agency (DISA), and provides service to the entire DoD community. Constituents of the DoD with questions about ASSIST or computer security issues, can contact ASSIST using one of the methods listed below. Non-DoD organizations/institutions, contact the Forum of Incident Response and Security Teams (FIRST) representative. To obtain a list of FIRST member organizations and their constituencies send an email to docserver@first.org with an empty "subject" line and a message body containing the line "send first-contacts". ASSIST Information Resources: To be included in the distribution list for the ASSIST bulletins, send your Milnet (Internet) e-mail address to assist-request@assist.mil. Back issues of ASSIST bulletins, and other security related information, are available from the ASSIST BBS at 703-607-4710, 327-4710, and through anonymous FTP from ftp.assist.mil (IP address 199.211.123.12). Note: ftp.assist.mil will only accept anonymous FTP connections from Milnet addresses that are registered with the NIC or DNS. If your system is not registered, you must provide your MILNET IP address to ASSIST before access can be provided. ASSIST Contact Information: PHONE: 800-357-4231, COMM 703-607-4700, DSN 327-4700. ELECTRONIC MAIL: assist@assist.mil. ASSIST BBS: COMM 703-607-4710, DSN 327-4710, leave a message for the "sysop". FAX: COMM 703-607-4735, DSN 607-4735 ASSIST uses Pretty Good Privacy (PGP) 2.6.2 as the digital signature mechanism for bulletins. PGP 2.6.2 incorporates the RSAREF(tm) Cryptographic Toolkit under license from RSA Data Security, Inc. A copy of that license is available via anonymous FTP from net-dist.mit.edu (IP 18.72.0.3) in the file /pub/PGP/rsalicen.txt, and through the world wide web from http://net-dist.mit.edu/pgp.html. In accordance with the terms of that license, PGP 2.6.2 may be used for non-commercial purposes only. Instructions for downloading the PGP 2.6.2 software can also be obtained from net-dist.mit.edu in the pub/PGP/README file. PGP 2.6.2 and RSAREF may be subject to the export control laws of the United States of America as implemented by the United States Department of State Office of Defense Trade Controls. The PGP signature information will be attached to the end of ASSIST bulletins. Reference herein to any specific commercial product, process, or service by trade name, trademark manufacturer, or otherwise, does not constitute or imply its endorsement, recommendation, or favoring by ASSIST. The views and opinions of authors expressed herein shall not be used for advertising or product endorsement purposes. -----BEGIN PGP SIGNATURE----- Version: 2.6 iQCVAwUBMhnbptH6sbnW3Io9AQHlrQP+KIgTPULQU7TYAv2W7/PR/Cq3AOzv3dUR s3nH2tChS+NFVu7AenrD6izMwH7ButI14zzZZ8OJLDpSeMN3QqA00F6Ofcj45+x+ r/wfikaoIaLqor18AMSZUTyk+ZMtLen1azjFAUy8pVgKckLPRXuvfP9iOFe2eTQn c4Rj7w4V3f4= =EH6g -----END PGP SIGNATURE----- **************************************************************************** * * * The point of contact for NIPRNET security-related incidents is the * * Security Coordination Center (SCC). * * * * E-mail address: SCC@NIC.DDN.MIL * * * * Telephone: 1-(800)-365-3642 * * * * NIC Help Desk personnel are available from 7:00 a.m.-7:00 p.m. EST, * * Monday through Friday except on federal holidays. * * * **************************************************************************** PLEASE NOTE: Some users outside of the DOD computing communities may receive DISN Security Bulletins. If you are not part of the DOD community, please contact your agency's incident response team to report incidents. Your agency's team will coordinate with DOD. The Forum of Incident Response and Security Teams (FIRST) is a world-wide organization. A list of FIRST member organizations and their constituencies can be obtained by sending email to docserver@first.org with an empty subject line and a message body containing the line: send first-contacts. This document was prepared as an service to the DOD community. Neither the United States Government nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, product, or process disclosed, or represents that its use would not infringe privately owned rights. 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