※ 本文轉錄自 [Lan] 信箱 作者: [email protected] (TWCERT/CC Fellows) 標題: 【TWCERT/CC安全通報】 TW-CA-2005-045-[FreeBSD- 時間: 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發布日期：2005-04-18 原漏洞發布日期：2005-04-15 原漏洞最新更新日期：-- 通用安全漏洞編號： 分類：Gain Privilege,Info Leak 來源參考：FreeBSD-SA-05:04.ifconf ──── 簡述 ───────────────────────────────── SIOCGIFCONF ioctl 允許使用者程序要求核心產生現有網路介面清單並複製到提供給 使用者程序使用的緩衝區。 ──── 說明 ───────────────────────────────── 在產生網路介面清單時，核心寫入部分緩衝區時並未事先做好歸零的動作。如此一來 ，緩衝區先前的內容將會洩漏給呼叫的程序。 ──── 影響平台 ─────────────────────────────── 受影響平台： 所有 FreeBSD 4.x 發行版本 所有 FreeBSD 5.x 5.4-RELEASE 之前的發行版本 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 ─────────────────────────────── 執行下列步驟： 1）將有弱點的系統升級至 4-STABLE, 5-STABLE, RELENG_5_3, RELENG_4_11 或 RELENG_4_10 2）修正您的系統 下列的修正步驟適合 FreeBSD 4.10, 4.11 及 5.3。 a)從下列位址下載目前的更新檔 [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) 執行更新 # cd /usr/src # patch < /path/to/patch c) 重新編譯核心 請參閱 http://www.freebsd.org/handbook/kernelconfig.html 並重新啟動系統。 ──── 影響結果 ─────────────────────────────── 最多 12 bytes 的核心記憶體資訊可能洩漏給使用者程序。這些記憶體可能包含敏感 資訊，例如檔案快取或終端緩衝區的部份。這些資訊也許直接有用或用來取得提高權 限。例如，終端緩衝區可能包含使用者輸入的密碼。 ──── 聯絡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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