6340740 2001-04-09 06:31 -0500 /199 rader/ Progeny Security Team <security@PROGENY.COM> Sänt av: joel@lysator.liu.se Importerad: 2001-04-09 20:07 av Brevbäraren Extern mottagare: BUGTRAQ@SECURITYFOCUS.COM Externa svar till: security@PROGENY.COM Mottagare: Bugtraq (import) <16418> Ärende: PROGENY-SA-2001-01: execve()/ptrace() exploit in Linux kernels ------------------------------------------------------------ prior to 2.2.19 From: Progeny Security Team <security@PROGENY.COM> To: BUGTRAQ@SECURITYFOCUS.COM Message-ID: <20010409113122.4F2391BDA0@andromeda.indy.progenylinux.com> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 --------------------------------------------------------------------------- PROGENY LINUX SYSTEMS -- SECURITY ADVISORY PROGENY-SA-2001-01 --------------------------------------------------------------------------- Topic: execve()/ptrace() exploit in Linux kernels prior to 2.2.19 Category: kernel Module: kernel-image-2.2.* Announced: 2001-04-04 Credits: Wojciech Purczynski <wp@elzabsoft.pl> BUGTRAQ <BUGTRAQ@securityfocus.com> Solar Designer <solar@openwall.com> Affects: Progeny Debian (Linux kernels prior to 2.2.19) Debian GNU/Linux (Linux kernels prior to 2.2.19) Vendor-Status: New Version Released (kernel 2.2.19) Corrected: 2001-04-02 Progeny Only: NO $Id: PROGENY-SA-2001-01,v 1.8 2001/04/09 08:38:10 csg Exp $ --------------------------------------------------------------------------- SYNOPSIS Linux kernels before 2.2.19 are vulnerable to a local root exploit. PROBLEM DESCRIPTION This vulnerability exploits a race condition in the 2.2.x Linux kernel within the execve() system call. By predicting the child-process sleep() within execve(), an attacker can use ptrace() or similar mechanisms to subvert control of the child process. If the child process is setuid, the attacker can cause the child process to execute arbitrary code at an elevated privilege. There are also other known lesser security issues with Linux kernels prior to 2.2.19 which have been noted as fixed in the solution listed below. Details can be found in the Security Updates section at: http://www.linux.org.uk/VERSION/relnotes.2219.html IMPACT Local users can use available exploits to gain root privileges. SOLUTION Upgrade to Linux kernel 2.2.19. You may use Progeny's kernel-image-2.2.19 package, version 1.81, for convenience. WORKAROUND No known workaround exists for this vulnerability. UPDATING VIA APT-GET 1. Ensure that your /etc/apt/sources.list file has a URI for Progeny's update repository: deb http://archive.progeny.com/progeny/updates newton/ 2. Update your cache of available packages for apt(8). Example: # apt-get update 3. Using apt(8), install the new kernel package. apt(8) will download the update, verify it's integrity with md5, and then install the package on your system with dpkg(8). Example: # apt-get install kernel-image-2.2.19 4. Since this update installs a new kernel, the security fixes cannot take effect until you reboot the system. When convenient, restart your system to start using the new kernel. Example: # shutdown -r now UPDATING VIA DPKG 1. Using your preferred FTP/HTTP client to retrieve the following updated files from Progeny's update archive at: http://archive.progeny.com/progeny/updates/newton/ Filename MD5 Checksum ------------------------------------ -------------------------------- kernel-image-2.2.19_1.81_i386.deb f72c383e22a064ec394cff50a84ab789 Example: # wget http://archive.progeny.com/progeny/updates/newton/kernel-image-2.2.19_1.81_i386.deb 2. Use the md5sum command on the retrieved file to verify that it matches the md5sum provided in this advisory: Example: # md5sum kernel-image-2.2.19_1.81_i386.deb 3. Then install the replacement package(s) using the dpkg command. Example: # dpkg --install kernel-image-2.2.19_1.81_i386.deb 4. Since this update installs a new kernel, the security fixes cannot take effect until you reboot the system. When convenient, restart your system to start using the new kernel. Example: # shutdown -r now MORE INFORMATION Linux kernels 2.4.0 and later are not affected by this problem. --------------------------------------------------------------------------- pub 1024D/F92D4D1F 2001-04-04 Progeny Security Team <security@progeny.com> - -----BEGIN PGP PUBLIC KEY BLOCK----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org mQGiBDrKpVkRBACS4/hjUliUt9UGTHMUGSZpQlKfBk9OFHmyLHTdjyIBCWRMmOBn RRhag0FgPicVIDndoQvYw3+ESC/RtbuPCBf6DZ7S0+NHhm1SHEbZyHFLkRXJm+IS 29oFmKrfXnXHckCrJFDZbOznRF6dVe7hV8CYi3FtoTjlRbuiHPQCMuy4ewCghAfv eYxfB25AoTdBT7WiG8jd4w8D/iFweuqzTwcWtXEgDbDd21W9hNPLEELgguimCCdP l3GHqw/MUJpIvdYfYhCzTaf4VpvkM5xlJGAcelCUL9qAufwyU8U8JI2YzlbqSlO8 qRwaiwq9qisTKEBb3IQadFqug+ihVdUeP8cuXPvbUEbFt7ILWyUD/kntgFdf1Apo zZWlA/0SM45hV6yomcM7z08tyh4hZTrWX/RUJqe+U1niNAmzPg4P+r8SfXdIkjb2 fZT5h5cYLIiK+kUEkqyPmZwUlgMCCn4IYVd2pcKXKXWE8ympuf3E5wGYeiVpLBM/ th7qdEF87sViV8McfiRuXEonYrs1nSQZX+f4OxvTQqaP46u10rQsUHJvZ2VueSBT ZWN1cml0eSBUZWFtIDxzZWN1cml0eUBwcm9nZW55LmNvbT6IVwQTEQIAFwUCOsql WQULBwoDBAMVAwIDFgIBAheAAAoJEEnBfSP5LU0f/sUAnjDpQs5SnFotNJ7GeIWx Ftf7AvBBAJ0cygWS0XRXxJJq2PKbCbdln+i4d7kEDQQ6yqcjEBAA465SSuC/yvN7 WeZAN9XperqZtxLCVe8hLfrLZ+9/Xn2ysuEEe90rYe1X0HbsB/mInHF3VmT+XvHB VdDQ7o0VMw7aeDgprt3jDQgT8gIesSOhZvulDujmLhykE+FT/V4lKpqO8prv7Ujs AfuC7g/X2dcV1+imNOeivLaCM0+HrwUhdvifWFDwE97wBkrda/vhu9zs3NwMeBVN UYfkRLPm+DGUSQVrteNiYJchhqfJB0mjrd+3FgnpCVgdU4c42epZ2ez/WTgTchoT duMCd1sM9gzvQIih56KzxlGL82PVS2m0PNxSQ8iZpheMMGWregjpjpMRcrRbSXy+ WmPBacOiE/MyxXand+lGzig/9Srm6msUT5jE/lDcfySznJWH8B/fqD7KM5Z0ZM+b 3xV0PzGyMld+m3BfGolqsd5bpo8HaWCWsZVYfgdXjoDPYptsoPdLesN6WIAHA1kU n2kckccz4xOoI/8MqKhkzZe0q5a9sv6RLBWDeVLxJnDuXZgcwCc4OvpcR4HnOE7c U5VsyjYwTkzGWWuQxb8uxng3akHTK2PqeZAnC0tvtuwI7QFhOq/dzz+zHzVH2+Qh 55Aq6DjA9yEs3P7g31wb3duGdWtuIXn+N85GiJdZ1EmJESQCuOYOSHsV4bGxKcpg PIpoSr5QBAUtUOTwN+xC8nNjZtC5OzsAAwYP/1OD/eiEraGpy7Z9scgXBjjb1kly tgq06zGlSMWPEQoN3F87YeMiOsXSeDxJG+cnhvlys1Qoytp9/drsDLANi+Q61A/b aka2IJLudiDu4iUDFb1rgRUERBciA31karPf2IwNjdU8lbulHfxQcjtjj7rbSWOG gxzlPcLp2F5ee3h0qs+XW4UpD6K9f/u9gGT4nMr3owG06uNomlBAsGCVpk9XlRxG x96161vrbmTPUx/o6NhqHNuf5Zh8ZmxQ3PYydywiE9njOtS04TTad24qbdPlVQh2 kjkTdsMCFRGaAB8EYImMT3F0ofon1Q/XWZrRlhkZpzuAKLhdSOW5G+tygNy2IqsH wCYa/rDitYZeNN4EUb5At4HnSBCy86GFQgj+sDFO6yp+h7NLIMeTm0csaSbKEt6o cbn0iMaRbLdHmAm0UHATPho+M2brf3mTztvAPONta2FC9TP1L1ojTDd4mtO9IcdM hjOVqNbuyLXkWgPcSmwhhjB61p3/1M1Y/zfXxLOsi/XJlstYzzKzHa68F1e9dTEz kgeYo1hG5TqMKv1sXfPJHw4N/QVcLoUlpUJZ/kI2OQD5mAhCCZ9PbT2fT4gLhy7U sn0blh/R/0HFSFDwHgmx8mNfw7w0qFbba9/FEE8D5qhyyCx5KTk0OkvRL9OpzO7E jzjdcfb6B2XpgSC8iEYEGBECAAYFAjrKpyMACgkQScF9I/ktTR90vgCggiX108DO S3rhSkmfFuHey8w4RlIAn3nD+uCe+sjCFqVwb+LY2jO3ybjB =6dRm - -----END PGP PUBLIC KEY BLOCK----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org iEYEARECAAYFAjrRglIACgkQScF9I/ktTR9AlACff1WSmqHEzw7R1YxJheylIVlc VYUAmQHBrhKSRLAUh+oM/j4DORe8i8vM =i3nx -----END PGP SIGNATURE----- (6340740) /Progeny Security Team <security@PROGENY.COM>/(Ombruten)