※ 本文转录自 [Lan] 信箱 作者: [email protected] (TWCERT/CC Fellows) 标题: 【TWCERT/CC安全通报】 TW-CA-2005-045-[FreeBSD- 时间: Mon Apr 18 17:06:44 2005 -----BEGIN PGP SIGNED MESSAGE----- TW-CA-2005-045-[FreeBSD-SA-05:04.ifconf: Kernel memory disclosure in ifconf()] ──────────────────────────────────────── TWCERT/CC发布日期：2005-04-18 原漏洞发布日期：2005-04-15 原漏洞最新更新日期：-- 通用安全漏洞编号： 分类：Gain Privilege,Info Leak 来源参考：FreeBSD-SA-05:04.ifconf ──── 简述 ───────────────────────────────── SIOCGIFCONF ioctl 允许使用者程序要求核心产生现有网路介面清单并复制到提供给 使用者程序使用的缓冲区。 ──── 说明 ───────────────────────────────── 在产生网路介面清单时，核心写入部分缓冲区时并未事先做好归零的动作。如此一来 ，缓冲区先前的内容将会泄漏给呼叫的程序。 ──── 影响平台 ─────────────────────────────── 受影响平台： 所有 FreeBSD 4.x 发行版本 所有 FreeBSD 5.x 5.4-RELEASE 之前的发行版本 已修正平台： 2005-04-15 01:51:44 UTC (RELENG_5, 5.4-STABLE) 2005-04-15 01:52:03 UTC (RELENG_5_4, 5.4-RELEASE) 2005-04-15 01:52:25 UTC (RELENG_5_3, 5.3-RELEASE-p9) 2005-04-15 01:52:40 UTC (RELENG_4, 4.11-STABLE) 2005-04-15 01:52:57 UTC (RELENG_4_11, 4.11-RELEASE-p3) 2005-04-15 01:53:14 UTC (RELENG_4_10, 4.10-RELEASE-p8) ──── 修正方式 ─────────────────────────────── 执行下列步骤： 1）将有弱点的系统升级至 4-STABLE, 5-STABLE, RELENG_5_3, RELENG_4_11 或 RELENG_4_10 2）修正您的系统 下列的修正步骤适合 FreeBSD 4.10, 4.11 及 5.3。 a)从下列位址下载目前的更新档 [FreeBSD 4.x] # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf4.patch # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf4.patch.asc [FreeBSD 5.x] # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf5.patch # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf5.patch.asc b) 执行更新 # cd /usr/src # patch < /path/to/patch c) 重新编译核心 请参阅 http://www.freebsd.org/handbook/kernelconfig.html 并重新启动系统。 ──── 影响结果 ─────────────────────────────── 最多 12 bytes 的核心记忆体资讯可能泄漏给使用者程序。这些记忆体可能包含敏感 资讯，例如档案快取或终端缓冲区的部份。这些资讯也许直接有用或用来取得提高权 限。例如，终端缓冲区可能包含使用者输入的密码。 ──── 联络TWCERT/CC ───────────────────────────── Tel: 886-7-5250211 FAX: 886-7-5250212 886-2-23563303 886-2-23924082 Email: [email protected] URL: http://www.cert.org.tw/ PGP key: http://www.cert.org.tw/eng/pgp.htm ──────────────────────────────────────── 附件：[Kernel memory disclosure in ifconf()] ──── 原文 ───────────────────────────────── ============================================================================= FreeBSD-SA-05:04.ifconf Security Advisory The FreeBSD Project Topic: Kernel memory disclosure in ifconf() Category: core Module: sys_net Announced: 2005-04-15 Credits: Ilja van Sprundel Affects: All FreeBSD 4.x releases All FreeBSD 5.x releases prior to 5.4-RELEASE Corrected: 2005-04-15 01:51:44 UTC (RELENG_5, 5.4-STABLE) 2005-04-15 01:52:03 UTC (RELENG_5_4, 5.4-RELEASE) 2005-04-15 01:52:25 UTC (RELENG_5_3, 5.3-RELEASE-p9) 2005-04-15 01:52:40 UTC (RELENG_4, 4.11-STABLE) 2005-04-15 01:52:57 UTC (RELENG_4_11, 4.11-RELEASE-p3) 2005-04-15 01:53:14 UTC (RELENG_4_10, 4.10-RELEASE-p8) For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:http://www.freebsd.org/security/>. I. Background The SIOCGIFCONF ioctl allows a user process to ask the kernel to produce a list of the existing network interfaces and copy it into a buffer provided by the user process. II. Problem Description In generating the list of network interfaces, the kernel writes into a portion of a buffer without first zeroing it. As a result, the prior contents of the buffer will be disclosed to the calling process. III. Impact Up to 12 bytes of kernel memory may be disclosed to the user process. Such memory might contain sensitive information, such as portions of the file cache or terminal buffers. This information might be directly useful, or it might be leveraged to obtain elevated privileges in some way. For example, a terminal buffer might include a user-entered password. IV. Workaround No known workaround. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to 4-STABLE or 5-STABLE, or to the RELENG_5_3, RELENG_4_11, or RELENG_4_10 security branch dated after the correction date. 2) To patch your present system: The following patches have been verified to apply to FreeBSD 4.10, 4.11, and 5.3 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. [FreeBSD 4.x] # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf4.patch # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf4.patch.asc [FreeBSD 5.3] # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf5.patch # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-05:04/ifconf5.patch.asc b) Apply the patch. # cd /usr/src # patch < /path/to/patch c) Recompile your kernel as described in and reboot the system. VI. Correction details The following list contains the revision numbers of each file that was corrected in FreeBSD. Branch Revision Path - - ------------------------------------------------------------------------- RELENG_4 src/sys/net/if.c 1.85.2.29 RELENG_4_11 src/UPDATING 1.73.2.91.2.4 src/sys/conf/newvers.sh 1.44.2.39.2.7 src/sys/net/if.c 1.85.2.28.2.1 RELENG_4_10 src/UPDATING 1.73.2.90.2.9 src/sys/conf/newvers.sh 1.44.2.34.2.10 src/sys/net/if.c 1.85.2.25.2.1 RELENG_5 src/sys/net/if.c 1.199.2.15 RELENG_5_4 src/UPDATING 1.342.2.24.2.3 src/sys/net/if.c 1.199.2.14.2.1 RELENG_5_3 src/UPDATING 1.342.2.13.2.12 src/sys/conf/newvers.sh 1.62.2.15.2.14 src/sys/net/if.c 1.199.2.7.2.3 - - ------------------------------------------------------------------------- The latest revision of this advisory is available at ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-05:04.ifconf.asc ──────────────────────────────────────── -----BEGIN PGP SIGNATURE----- Version: PGP 7.0.4 iQEVAwUBQmN4JqcyQYefg2/NAQGrxggAhl9lBPKAQlYhOZJP//YOoYrRp0S7O19y UX1Q6QXJ4zNOoB8h4J0d+PhIUCykCLnNhMxUg7aZaqmsMsDPR7xAlTPlAxEhEWPR a8wLeN6TwNg96lPBS4HPdMaFIduiz5HvwqeaxAMO9B+jgxeT4IIi3SzzaqiBTnb/ KJVHPxhUATNs7HsXhKlag4qCG6D8bR5Ou6tgl8NoHhF9i8F7ebDeX7sEc777NOfF FOG9o6J0fGrEqlrk35fmWhcXTZgHntoDIDzjIzK+KYr6THrcUAe2kyfq7z9SCizY gl1avgdcFmXXmJNSRwaFJuWWfHtmcC60i0kszK91UDrLxf2GSML3dg== =pSrQ -----END PGP SIGNATURE----- -- Taiwan Computer Emergency Response Team Security Advisory mailing list. 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