6361692 2001-04-13 11:05 -0500 /207 rader/ Progeny Security Team <security@PROGENY.COM> Sänt av: joel@lysator.liu.se Importerad: 2001-04-14 00:46 av Brevbäraren Extern mottagare: BUGTRAQ@SECURITYFOCUS.COM Externa svar till: security@PROGENY.COM Mottagare: Bugtraq (import) <16534> Ärende: PROGENY-SA-2001-02A: [UPDATE] ntpd remote buffer overflow ------------------------------------------------------------ From: Progeny Security Team <security@PROGENY.COM> To: BUGTRAQ@SECURITYFOCUS.COM Message-ID: <20010413160550.9905C1404B@albus.indy.progeny.com> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 --------------------------------------------------------------------------- PROGENY LINUX SYSTEMS -- SECURITY ADVISORY PROGENY-SA-2001-02A --------------------------------------------------------------------------- Topic: ntpd remote buffer overflow Category: net Module: ntp Announced: 2001-04-09 Credits: Przemyslaw Frasunek <venglin@FREEBSD.LUBLIN.PL> BUGTRAQ <BUGTRAQ@securityfocus.com> Poul-Henning Kamp <phk@freebsd.org> Affects: Progeny Debian (ntp prior to 4.0.99g-2.0progeny6) Debian GNU/Linux (ntp prior to 4.0.99g-2potato2) Vendor-Status: New Version Released (ntp_4.0.99g-2.0progeny6) Corrected: 2001-04-12 Progeny Only: NO $Id: PROGENY-SA-2001-02,v 1.11 2001/04/13 15:54:28 jdaily Exp $ --------------------------------------------------------------------------- UPDATE SYNOPSIS This is an update to advisory PROGENY-SA-2001-02. The original fix for the ntpd vulnerability described below introduced a potential denial of service. This has been corrected in a new package, ntp_4.0.99g-2.0progeny6. SYNOPSIS Versions of the Network Time Protocol Daemon (ntpd) previous to and including 4.0.99k have a remote buffer overflow which may lead to a remote root exploit. PROBLEM DESCRIPTION The Network Time Protocol Daemon is vulnerable to a remote buffer overflow attack which could potentially be exploited to gain remote root access. The buffer overflow occurs when building a response to a query with a large readvar argument. The shellcode executed must be less than 70 bytes, otherwise the destination buffer is damaged. This makes the vulnerability difficult but not impossible to exploit. Furthermore, it should be noted that it is easy to spoof the source address of potential malicious queries to an ntp server. IMPACT Remote users could adapt available exploits to gain root privileges. SOLUTION Upgrade to a fixed version of ntpd. You may use Progeny's ntp package, version 4.0.99g-2.0progeny6, 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 security 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 package. apt(8) will download the update, verify its integrity with md5, and then install the package on your system with dpkg(8). Example: # apt-get install ntp 4. Since this update installs a new version of the ntp daemon, we recommend restarting it following installation to make certain the old version is not still running. Example: # /etc/init.d/ntp restart 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 ------------------------------------ -------------------------------- ntp_4.0.99g-2.0progeny6_i386.deb 8ce73b29f7d4b77dda190c3b31c42255 Example: # wget http://archive.progeny.com/progeny/updates/newton/ntp_4.0.99g-2.0progeny6_i386.deb 2. Use the md5sum command on the retrieved file to verify that it matches the md5sum provided in this advisory: Example: # md5sum ntp_4.0.99g-2.0progeny6_i386.deb 3. Then install the replacement package(s) using the dpkg command. Example: # dpkg --install ntp_4.0.99g-2.0progeny6_i386.deb 4. Since this update installs a new version of the ntp daemon, we recommend restarting it following installation to make certain the old version is not still running. Example: # /etc/init.d/ntp restart MORE INFORMATION While (reportedly) all upstream versions of ntp previous to and including 4.0.99k are vulnerable, the Progeny Debian 4.0.99g-2.0progeny6 and Debian GNU/Linux 4.0.99g-2potato2 packages have been patched to fix 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 iEYEARECAAYFAjrXIYMACgkQScF9I/ktTR9qegCeLQDhnS7AznAtBONiKyZUp1Lp 2DAAnRmwpHL42mgAbUMV0wNaT3pgMBJC =6H5t -----END PGP SIGNATURE----- (6361692) /Progeny Security Team <security@PROGENY.COM>/(Ombruten) Kommentar i text 6361693