Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2003.0556 -- RHSA-2003:255-01 up2date improperly checks GPG signature of packages 11 August 2003 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: up2date Publisher: Red Hat Operating System: Red Hat Linux 9 Red Hat Linux 8.0 Impact: Reduced Security Access Required: Remote CVE Names: CAN-2003-0546 - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 - - --------------------------------------------------------------------- Red Hat Security Advisory Synopsis: up2date improperly checks GPG signature of packages Advisory ID: RHSA-2003:255-01 Issue date: 2003-08-08 Updated on: 2003-08-08 Product: Red Hat Linux Keywords: up2date gpg Red Hat Network RHN rpm Cross references: Obsoletes: CVE Names: CAN-2003-0546 - - --------------------------------------------------------------------- 1. Topic: Updated up2date packages for Red Hat Linux 8.0 and 9 fix RPM GPG signature verification. 2. Relevant releases/architectures: Red Hat Linux 8.0 - i386 Red Hat Linux 9 - i386 3. Problem description: The Red Hat Update Agent, up2date, automatically queries the Red Hat Network servers and determines which packages need to be updated on your machine. up2date versions 3.0.7 and 3.1.23 incorrectly check RPM GPG signatures. These are the versions found in Red Hat Linux 8.0 and 9. This bug allows packages which have no GPG signature to be installed by up2date if they are provided by the Red Hat Network servers. The intended behaviour is that only packages signed with the Red Hat package signing key will be installed. For an attacker to make use of this flaw, they would have to make unsigned packages appear on the Red Hat Network. Connections to the Red Hat Network servers are authenticated and verified by the use of SSL, so it is not possible to intercept the connection to Red Hat Network servers and give unsigned packages. To make use of this flaw, an attacker would have to compromise the Red Hat Network servers at Red Hat. Because of these factors, the risk of exploiting this bug is low. However, we advise that all users of up2date update to these erratum packages. Note that all other variations of package signature checks work correctly. The fix was to change the code so that packages with no GPG signature are rejected in the same way as those with bad GPG signatures (the up2date client refuses to install them). Red Hat would like to thank Barry Nathan for finding and reporting this error. 4. 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. 5. RPMs required: Red Hat Linux 8.0: SRPMS: ftp://updates.redhat.com/8.0/en/os/SRPMS/up2date-3.0.7.1-2.src.rpm i386: ftp://updates.redhat.com/8.0/en/os/i386/up2date-3.0.7.1-2.i386.rpm ftp://updates.redhat.com/8.0/en/os/i386/up2date-gnome-3.0.7.1-2.i386.rpm Red Hat Linux 9: SRPMS: ftp://updates.redhat.com/9/en/os/SRPMS/up2date-3.1.23.1-5.src.rpm i386: ftp://updates.redhat.com/9/en/os/i386/up2date-3.1.23.1-5.i386.rpm ftp://updates.redhat.com/9/en/os/i386/up2date-gnome-3.1.23.1-5.i386.rpm 6. Verification: MD5 sum Package Name - - -------------------------------------------------------------------------- 606193c00a7fb419b4952b68f1245082 8.0/en/os/SRPMS/up2date-3.0.7.1-2.src.rpm be91944cf454244846a96b94a3efaa74 8.0/en/os/i386/up2date-3.0.7.1-2.i386.rpm 0adeb9cf7fff1754d183894fa40111bc 8.0/en/os/i386/up2date-gnome-3.0.7.1-2.i386.rpm 99d3b05223b596cf8d949c27b48e2ebd 9/en/os/SRPMS/up2date-3.1.23.1-5.src.rpm c6e89c3f118b5734a34d7275d8156596 9/en/os/i386/up2date-3.1.23.1-5.i386.rpm bf0b79cfeaaa6ed947609a27da5c2d65 9/en/os/i386/up2date-gnome-3.1.23.1-5.i386.rpm These packages are GPG signed by Red Hat for security. Our key is available from http://www.redhat.com/security/keys.html You can verify each package 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> 7. References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0546 8. Contact: The Red Hat security contact is <secalert@redhat.com>. More contact details at http://www.redhat.com/solutions/security/news/contact.html Copyright 2003 Red Hat, Inc. - -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.7 (GNU/Linux) iD8DBQE/M9GWXlSAg2UNWIIRAvj6AJ9vxYutNeN6thdPT+ahlT1znB/eGQCdHXD+ xaGoUfY5bmYFoCJXN+gU158= =x/iL - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 If you believe that your computer system has been compromised or attacked in any way, we encourage you to let us know by completing the secure National IT Incident Reporting Form at: http://www.auscert.org.au/render.html?it=3192 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBPzcwYCh9+71yA2DNAQGW2QP/WywbVBoqhOlxzYtsii85saoDz3Yl9pnS 2P91jZsaQTAvebT9bhout1u7htyPkwZcep9u6I7WEgZJ/+prFjQVVgoxZJ3+UzCS Dj11wHejSY2uxh5IaBu2ALXGFr2yrW7Yp6bzvTFoC9P9Y/Idzh7czZwTHEtZK4Qp u7uxEL7yFyg= =wi7K -----END PGP SIGNATURE-----