-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ______________________________________________________________________________ SCO Security Advisory Subject: UnixWare 7.1.3 Open UNIX 8.0.0 UnixWare 7.1.1 : Insecure handling of procfs descriptors in UnixWare can lead to local privilege escalation. Advisory number: CSSA-2003-SCO.32 Issue date: 2003 November 11 Cross reference: sr886899 fz528474 erg712482 ______________________________________________________________________________ 1. Problem Description "/proc/$PID/as" Contains the address space image of process $PID. It can be opened and accessed like any other file and be used to manipulate the process. The process owner also owns the "as" file whose file permission is 600. For obvious reasons this doesn't apply to processes spawned from setuid and setgid binaries. This protection can be bypassed by first obtaining a descriptor to a process you own then let that process execve() a setuid binary. execve() will replace the process image, honor the setuid bit and the descriptor will remain open. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2003-0937 to this issue. 2. Vulnerable Supported Versions System Binaries ---------------------------------------------------------------------- UnixWare 7.1.3 /etc/conf/pack.d/procfs/Driver_atup.o /etc/conf/pack.d/procfs/Driver_mp.o Open UNIX 8.0.0 /etc/conf/pack.d/procfs/Driver_atup.o (aka UnixWare 7.1.2) /etc/conf/pack.d/procfs/Driver_mp.o UnixWare 7.1.1 /etc/conf/pack.d/procfs/Driver_atup.o /etc/conf/pack.d/procfs/Driver_mp.o 3. Solution The proper solution is to install the latest packages. 4. UnixWare 7.1.3 4.1 Location of Fixed Binaries ftp://ftp.sco.com/pub/updates/UnixWare/CSSA-2003-SCO.32 erg712482c should only be installed on: UnixWare 7.1.3 4.2 Verification MD5 (erg712482c.Z) = 50c98884a6dcb14ccf57d71aad135045 md5 is available for download from ftp://ftp.sco.com/pub/security/tools 4.3 Installing Fixed Binaries Upgrade the affected binaries with the following sequence: 1. Download the erg712482c.Z file to the /tmp directory on your machine. 2. As root, uncompress the file and add the package to your system using these commands: $ su Password: # uncompress /tmp/erg712482c.Z # pkgadd -d /tmp/erg712482c # rm /tmp/erg712482c Alternatively, this SLS package may be installed in quiet mode, that is, without displaying the release notes and asking for confirmation. To do this, use these commands: $ su Password: # uncompress /tmp/erg712482c.Z # pkgadd -qd /tmp/erg712482c all # rm /tmp/erg712482c 3. Reboot the system after installing this package. Removal Instructions -------------------- 1. As root, remove the package using these commands: $ su Password: # pkgrm erg712482 2. Reboot the system after removing this package. 5. Open UNIX 8.0.0 5.1 Location of Fixed Binaries ftp://ftp.sco.com/pub/updates/UnixWare/CSSA-2003-SCO.32 erg712482b should only be installed on: UnixWare 7.1.2 or Open UNIX 8.0.0 5.2 Verification MD5 (erg712482b.Z) = 54d3568e631d4739034815537242dc0d md5 is available for download from ftp://ftp.sco.com/pub/security/tools 5.3 Installing Fixed Binaries Upgrade the affected binaries with the following sequence: 1. Download the erg712482b.Z file to the /tmp directory on your machine. 2. As root, uncompress the file and add the package to your system using these commands: $ su Password: # uncompress /tmp/erg712482b.Z # pkgadd -d /tmp/erg712482b # rm /tmp/erg712482b Alternatively, this SLS package may be installed in quiet mode, that is, without displaying the release notes and asking for confirmation. To do this, use these commands: $ su Password: # uncompress /tmp/erg712482b.Z # pkgadd -qd /tmp/erg712482b all # rm /tmp/erg712482b 3. Reboot the system after installing this package. Removal Instructions -------------------- 1. As root, remove the package using these commands: $ su Password: # pkgrm erg712482 2. Reboot the system after removing this package. 6. UnixWare 7.1.1 6.1 Location of Fixed Binaries ftp://ftp.sco.com/pub/updates/UnixWare/CSSA-2003-SCO.32 erg712482a should only be installed on: UnixWare 7.1.1 6.2 Verification MD5 (erg712482a.Z) = 15776bcbaf01155eb28087ee213fecf8 md5 is available for download from ftp://ftp.sco.com/pub/security/tools 6.3 Installing Fixed Binaries Upgrade the affected binaries with the following sequence: erg712482a should only be installed on: UnixWare 7.1.1 1. Download the erg712482a.Z file to the /tmp directory on your machine. 2. As root, uncompress the file and add the package to your system using these commands: $ su Password: # uncompress /tmp/erg712482a.Z # pkgadd -d /tmp/erg712482a # rm /tmp/erg712482a Alternatively, this SLS package may be installed in quiet mode, that is, without displaying the release notes and asking for confirmation. To do this, use these commands: $ su Password: # uncompress /tmp/erg712482a.Z # pkgadd -qd /tmp/erg712482a all # rm /tmp/erg712482a 3. Reboot the system after installing this package. Removal Instructions -------------------- 1. As root, remove the package using these commands: $ su Password: # pkgrm erg712482 2. Reboot the system after removing this package. 7. References Specific references for this advisory: http://www.texonet.com/advisories/TEXONET-20031024.txt http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0937 SCO security resources: http://www.sco.com/support/security/index.html This security fix closes SCO incidents sr886899 fz528474 erg712482. 8. Disclaimer SCO is not responsible for the misuse of any of the information we provide on this website and/or through our security advisories. Our advisories are a service to our customers intended to promote secure installation and use of SCO products. 9. Acknowledgments SCO would like to thank Joel Soderberg and Christer Oberg from Texonet. Texonet is a Swedish based security company with a focus on penetration testing / security assessments, research and development. ______________________________________________________________________________ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.3 (SCO/UNIX_SVR5) iD8DBQE/sVF8aqoBO7ipriERAnHfAJ9MyE3uuzUpvoWxw/ALWgKoF9khmwCgnU2H n7SUQXgTFmXShKAXoxTN3F0= =Ow6H -----END PGP SIGNATURE-----