Published:
19 March 2000
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-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2000.050 -- FreeBSD-SA-00:10 orville-write port contains local root compromise 20 March 2000 =========================================================================== The FreeBSD Security Team has released the following security advisory describing a vulnerability in the orville-write package which is a replacement for the write(1) command. The 'huh' command was incorrectly configured with setuid root privilege. This vulnerability may be exploited by a local user to gain root privilege on affected systems. - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-00:10 Security Advisory FreeBSD, Inc. Topic: orville-write port contains local root compromise. Category: ports Module: orville-write Announced: 2000-03-15 Affects: Ports collection before the correction date. Corrected: 2000-03-09 FreeBSD only: Yes I. Background Orville-write is a replacement for the write(1) command, which provides improved control over message delivery and other features. II. Problem Description One of the commands installed by the port is incorrectly installed with setuid root permissions. The 'huh' command should not have any special privileges since it is intended to be run by the local user to view his saved messages. The orville-write port is not installed by default, nor is it "part of FreeBSD" as such: it is part of the FreeBSD ports collection, which contains over 3100 third-party applications in a ready-to-install format. The FreeBSD 4.0-RELEASE ports collection is not vulnerable to this problem. FreeBSD makes no claim about the security of these third-party applications, although an effort is underway to provide a security audit of the most security-critical ports. III. Impact A local user can exploit a buffer overflow in the 'huh' utility to obtain root privileges. If you have not chosen to install the orville-write port/package, then your system is not vulnerable. IV. Workaround Remove the orville-write port if you have installed it. V. Solution Remove the setuid bit from the huh utility, by executing the following command as root: chmod u-s /usr/local/bin/huh It is not necessary to reinstall the orville-write port, although this can be done in one of the following ways if desired: 1) Upgrade your entire ports collection and rebuild the orville-write port. 2) Reinstall a new package dated after the correction date, obtained from: ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/misc/orville-write-2.41a.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-current/misc/orville-write-2.41a.tgz ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/alpha/packages-4-current/misc/orville-write-2.41a.tgz Note: it may be several days before the updated packages are available. 3) download a new port skeleton for the orville-write port from: http://www.freebsd.org/ports/ and use it to rebuild the port. 4) Use the portcheckout utility to automate option (3) above. The portcheckout port is available in /usr/ports/devel/portcheckout or the package can be obtained from: ftp://ftp.freebsd.org/pub/FreeBSD/ports/packages/devel/portcheckout-1.0.tgz - -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBOM/KWlUuHi5z0oilAQHk3AP+PEWNZ95ou8Oyf0nFzgAvjRCc4T060cJf 8qncBFmbWKvl/VHGJnj+u5HPE2LciZb/SdQxH0Ibuvm45hjt7umRrNcHQABmhtYV 9kG2k2cG+w9QtPnWQUtk7UDAQ2nmbyvQBsUJI+wrILoTHaKU1nLBivzzQbZPX9Nr YTNtkrInpV0= =c84W - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- 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 use any or all of this information is the responsibility of each user or organisation, and should be done so in accordance with site policies and procedures. 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 original authors 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/Information/advisories.html If you believe that your system has been compromised, contact AusCERT or your representative in FIRST (Forum of Incident Response and Security Teams). 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 emergencies. -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv Comment: ftp://ftp.auscert.org.au/pub/auscert/AUSCERT_PGP.key iQCVAwUBONiZCSh9+71yA2DNAQHQmQP+Lt7sV+GkmGfJw+bCWzNj+4C8LtQQJLD3 X99SJ4OHC5LzXyQKB+0sdarocoBSJfKnCAVbvhj74ZC1ci2KUqRhnqOyLkbJi7IT hWfxz1/curJYwTBb4x8LS93peJ2JgBFReP+42iAPsOZ1VV2jmgBf1AehyCP4Wtel 0onb2AM5bRY= =E78O -----END PGP SIGNATURE-----