__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Red Hat Updated unzip Packages Fix Trojan Vulnerability [Red Hat Security Advisory RHSA-2003:199-05] July 1, 2003 18:00 GMT Number N-111 [Revised 14 Aug 2003] ______________________________________________________________________________ PROBLEM: Unzip versions 5.50 and earlier contain a vulnerability allowing arbitrary files to be overwritten during extraction. PLATFORM: Red Hat Linux 7.1, 7.2, 7.3, 8.0 and 9 DAMAGE: Attackers could place non-printable characters in malicious .zip files making it possible to write to parent directories. SOLUTION: Update to the new unzip packages listed in the advisory. ______________________________________________________________________________ VULNERABILITY The risk is MEDIUM. Users would have to click on an unzipped ASSESSMENT: file to initiate the malicious action. Users should always be cautious with e-mail attachments including .zip files. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/n-111.shtml ORIGINAL BULLETIN: https://rhn.redhat.com/errata/RHSA-2003-199.html ADDITIONAL INFORMATION: http://www.sunsolve.sun.com/pub-cgi/retrieve.pl?doc= fsalert%2F56120&zone_32=category%3Asecurity ______________________________________________________________________________ Revision History: 08/14/03 - Added Sun's Alert ID: 56120 [***** Start Red Hat Security Advisory RHSA-2003:199-05 *****] Updated unzip packages fix trojan vulnerability Advisory: RHSA-2003:199-05 Last updated on: 2003-07-01 Affected Products: Red Hat Linux 7.1 Red Hat Linux 7.2 Red Hat Linux 7.3 Red Hat Linux 8.0 Red Hat Linux 9 CVEs (cve.mitre.org): CAN-2003-0282 Security Advisory Details: Updated unzip packages resolving a vulnerability allowing arbitrary files to be overwritten are now available. The unzip utility is used for manipulating archives, which are multiple files stored inside of a single file. A vulnerabilitiy in unzip version 5.50 and earlier allows attackers to overwrite arbitrary files during archive extraction by placing invalid (non-printable) characters between two "." characters. These non-printable characters are filtered, resulting in a ".." sequence. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2003-0282 to this issue. This erratum includes a patch ensuring that non-printable characters do not make it possible for a malicious .zip file to write to parent directories unless the "-:" command line parameter is specified. Users of unzip are advised to upgrade to these updated packages, which are not vulnerable to this issue. Updated packages: Red Hat Linux 7.1 -------------------------------------------------------------------------------- SRPMS: unzip-5.50-11.src.rpm [ via FTP ] [ via HTTP ] 627c65d2643152f360a4b7f8ebacf993 i386: unzip-5.50-11.i386.rpm [ via FTP ] [ via HTTP ] c37b3635f768ca248ef6486f38a4cfb1 Red Hat Linux 7.2 -------------------------------------------------------------------------------- SRPMS: unzip-5.50-11.src.rpm [ via FTP ] [ via HTTP ] 627c65d2643152f360a4b7f8ebacf993 i386: unzip-5.50-11.i386.rpm [ via FTP ] [ via HTTP ] c37b3635f768ca248ef6486f38a4cfb1 ia64: unzip-5.50-11.ia64.rpm [ via FTP ] [ via HTTP ] e1cb9d0c5312667c601e3a04e160ea3c Red Hat Linux 7.3 -------------------------------------------------------------------------------- SRPMS: unzip-5.50-11.src.rpm [ via FTP ] [ via HTTP ] 627c65d2643152f360a4b7f8ebacf993 i386: unzip-5.50-11.i386.rpm [ via FTP ] [ via HTTP ] c37b3635f768ca248ef6486f38a4cfb1 Red Hat Linux 8.0 -------------------------------------------------------------------------------- SRPMS: unzip-5.50-12.src.rpm [ via FTP ] [ via HTTP ] b06d287ae9708615d9c8201addd84ceb i386: unzip-5.50-12.i386.rpm [ via FTP ] [ via HTTP ] 14e662c115aab0fd073602a2637c306a Red Hat Linux 9 -------------------------------------------------------------------------------- SRPMS: unzip-5.50-14.src.rpm [ via FTP ] [ via HTTP ] da4837981a5363b178185c3d53bfe3f5 i386: unzip-5.50-14.i386.rpm [ via FTP ] [ via HTTP ] 12b5697f11ad09959e9f51d570c37268 Solution Before applying this update, make sure all previously released errata relevant to your system have been applied. To update all RPMs for your particular architecture, run: rpm -Fvh [filenames] where [filenames] is a list of the RPMs you wish to upgrade. Only those RPMs which are currently installed will be updated. Those RPMs which are not installed but included in the list will not be updated. Note that you can also use wildcards (*.rpm) if your current directory *only* contains the desired RPMs. Please note that this update is also available via Red Hat Network. Many people find this an easier way to apply updates. To use Red Hat Network, launch the Red Hat Update Agent with the following command: up2date This will start an interactive process that will result in the appropriate RPMs being upgraded on your system. Bugs fixed: (see bugzilla for more information) 97301 - vulnerability in unzip 5.50 allows malicious zip file to write to ../ References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0282 http://marc.theaimsgroup.com/?l=bugtraq&m=105259038503175 Keywords: characters, control, unzip -------------------------------------------------------------------------------- The listed packages are GPG signed by Red Hat, Inc. for security. Our key is available at: http://www.redhat.com/solutions/security/news/publickey/#key You can verify each package and see who signed it with the following command: rpm --checksig -v filename If you only wish to verify that each package has not been corrupted or tampered with, examine only the md5sum with the following command: md5sum filename The Red Hat security contact is security@redhat.com. More contact details at http://www.redhat.com/solutions/security/news/contact.html [***** End Red Hat Security Advisory RHSA-2003:199-05 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Red Hat, Inc. for the information contained in this bulletin. _______________________________________________________________________________ CIAC, the Computer Incident Advisory Capability, is the computer security incident response team for the U.S. Department of Energy (DOE) and the emergency backup response team for the National Institutes of Health (NIH). CIAC is located at the Lawrence Livermore National Laboratory in Livermore, California. CIAC is also a founding member of FIRST, the Forum of Incident Response and Security Teams, a global organization established to foster cooperation and coordination among computer security teams worldwide. CIAC services are available to DOE, DOE contractors, and the NIH. CIAC can be contacted at: Voice: +1 925-422-8193 (7x24) FAX: +1 925-423-8002 STU-III: +1 925-423-2604 E-mail: ciac@ciac.org Previous CIAC notices, anti-virus software, and other information are available from the CIAC Computer Security Archive. World Wide Web: http://www.ciac.org/ Anonymous FTP: ftp.ciac.org PLEASE NOTE: Many users outside of the DOE, ESnet, and NIH computing communities receive CIAC bulletins. If you are not part of these communities, please contact your agency's response team to report incidents. Your agency's team will coordinate with CIAC. 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 via WWW at http://www.first.org/. This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. 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