发布时间 :2001-09-20 00:00:00
修订时间 :2008-09-05 16:25:30

[原文]libutil in OpenSSH on FreeBSD 4.4 and earlier does not drop privileges before verifying the capabilities for reading the copyright and welcome files, which allows local users to bypass the capabilities checks and read arbitrary files by specifying alternate copyright or welcome files.

[CNNVD]FreeBSD OpenSSH libutil读取任意文漏洞(CNNVD-200109-096)

        FreeBSD 4.4以及之前版本中OpenSSH的libutil在核查阅读版权和欢迎文件功能之前不能下降特权。本地用户通过指定替代版权或者欢迎文件绕过功能检查并读取任意文件。

- CVSS (基础分值)

CVSS分值: 2.1 [轻微(LOW)]
机密性影响: PARTIAL [很可能造成信息泄露]
完整性影响: NONE [不会对系统完整性产生影响]
可用性影响: NONE [对系统可用性无影响]
攻击复杂度: LOW [漏洞利用没有访问限制 ]
攻击向量: LOCAL [漏洞利用需要具有物理访问权限或本地帐户]
身份认证: NONE [漏洞利用无需身份认证]

- CPE (受影响的平台与产品)

cpe:/o:freebsd:freebsd:4.4FreeBSD 4.4
cpe:/a:openbsd:openssh:4.5OpenBSD OpenSSH 4.5

- OVAL (用于检测的技术细节)


- 官方数据库链接
(官方数据源) MITRE
(官方数据源) NVD
(官方数据源) CNNVD

- 其它链接及资源
(VENDOR_ADVISORY)  XF  bsd-libutil-privilege-dropping(8697)
(UNKNOWN)  BUGTRAQ  20010920 Local vulnerability in libutil derived with FreeBSD 4.4-RC (and earlier)

- 漏洞信息

FreeBSD OpenSSH libutil读取任意文漏洞
低危 未知
2001-09-20 00:00:00 2006-03-28 00:00:00
        FreeBSD 4.4以及之前版本中OpenSSH的libutil在核查阅读版权和欢迎文件功能之前不能下降特权。本地用户通过指定替代版权或者欢迎文件绕过功能检查并读取任意文件。

- 公告与补丁


- 漏洞信息 (21114)

FreeBSD 4.3/4.4 Login Capabilities Privileged File Reading Vulnerability (EDBID:21114)
freebsd local
2001-09-17 Verified
0 Przemyslaw Frasunek
N/A [点击下载]

FreeBSD is a freely available, open source implementation of the BSD UNIX Operating System. It is developed and maintained by the FreeBSD Project.

It is possible for a user with access to a system via SSH to gain access to privileged information. This problem is caused by a mixture of problems with login capabilities, the FreeBSD OpenSSH port not dropping privileges during part of the login process, and login not dropping privileges at the correct time. A user could make a malicious entry in the .login.conf file in their home directoy, and read files such as the master.passwd file and gain access to encrypted passwords on the system.

This issue does not appear to affect other BSD distributions. 

In a .login.conf entry contained in a home directory, make the following entry if accessing the system via OpenSSH:

default: :copyright=/etc/master.passwd:



Otherwise, if accessing the system via login, make the following entry in a .login.conf:

default: :nologin=/etc/master.passwd: 		

- 漏洞信息

OpenSSH on FreeBSD libutil Arbitrary File Read
Local Access Required Information Disclosure, Input Manipulation
Loss of Confidentiality
Exploit Public

- 漏洞描述

OpenSSH on FreeBSD platforms contains a flaw that may lead to an unauthorized information disclosure. The issue is triggered when the user sets welcome or copyright file parameters to system-sensitive files in their login.conf, which will disclose the contents of those files to that user, resulting in a loss of confidentiality.

- 时间线

2001-09-20 Unknow
2001-09-20 Unknow

- 解决方案

Upgrade to version 4.4-RELEASE or higher, as it has been reported to fix this vulnerability. It is also possible to correct the flaw by applying the vendor-supplied patch.

- 相关参考

- 漏洞作者