发布时间 :2014-03-31 10:58:57
修订时间 :2014-03-31 14:59:53

[原文]Untrusted search path vulnerability in the CyanogenMod/ClockWorkMod/Koush Superuser package for Android 4.2.x and earlier allows attackers to trigger the launch of a Trojan horse app_process program via a crafted PATH environment variable for a /system/xbin/su process.

[CNNVD]ClockWorkMod Superuser Package Environment Search Path 本地提权漏洞(CNNVD-201311-222)

        ClockWorkMod Superuser是一套安卓手机超级用户授权工具。该工具通过授予应用程序root权限,可掌握手机的控制权。
        ClockWorkMod Superuser工具包中存在本地提权漏洞。攻击者可利用该漏洞以root权限执行命令。ClockWorkMod Superuser版本中存在漏洞,其他版本也可能受到影响。

- CVSS (基础分值)

CVSS分值: 5 [中等(MEDIUM)]
机密性影响: NONE [对系统的机密性无影响]
完整性影响: PARTIAL [可能会导致系统文件被修改]
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: NETWORK [攻击者不需要获取内网访问权或本地访问权]
身份认证: NONE [漏洞利用无需身份认证]

- CWE (弱点类目)

CWE-22 [对路径名的限制不恰当(路径遍历)]

- 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  20131113 Superuser unsanitized environment vulnerability on Android <= 4.2.x

- 漏洞信息

ClockWorkMod Superuser Package Environment Search Path 本地提权漏洞
2013-11-21 00:00:00 2013-11-21 00:00:00
        ClockWorkMod Superuser是一套安卓手机超级用户授权工具。该工具通过授予应用程序root权限,可掌握手机的控制权。
        ClockWorkMod Superuser工具包中存在本地提权漏洞。攻击者可利用该漏洞以root权限执行命令。ClockWorkMod Superuser版本中存在漏洞,其他版本也可能受到影响。

- 公告与补丁


- 漏洞信息 (F124015)

Android 4.2.x Superuser Unsanitized Environment (PacketStormID:F124015)
2013-11-14 00:00:00
Kevin Cernekee  

Vulnerable releases of several common Android Superuser packages may allow malicious Android applications to execute arbitrary commands as root without notifying the device owner. This advisoriy documents PATH and BOOTCLASSPATH vulnerabilities.

Vulnerable releases of several common Android Superuser packages may
allow malicious Android applications to execute arbitrary commands as
root without notifying the device owner:

 - ChainsDD Superuser (current releases, including v3.1.3)
 - CyanogenMod/ClockWorkMod/Koush Superuser (current releases,
including v1.0.2.1)
 - Chainfire SuperSU prior to v1.69

The majority of third-party ROMs include one of these packages.

On a rooted Android <= 4.2.x device, /system/xbin/su is a setuid root
binary which performs a number of privilege checks in order to
determine whether the operation requested by the caller should be
allowed.  In the course of its normal duties, and prior to making the
allow/deny decision, /system/xbin/su invokes external programs under a
privileged UID, typically root (0) or system (1000):

 - /system/bin/log, to record activity to logcat
 - /system/bin/am, to send intents to the Superuser Java app
 - /system/bin/sh, to execute the /system/bin/am wrapper script
 - /system/bin/app_process, the Dalvik VM

The user who invokes /system/xbin/su may have the ability to
manipulate the environment variables, file descriptors, signals,
rlimits, tty/stdin/stdout/stderr, and possibly other items belonging
to any of these subprocesses.  At least two vulnerabilities are
readily apparent:

 - On ClockWorkMod Superuser, /system/xbin/su does not set PATH to a
known-good value, so a malicious user could trick /system/bin/am into
using a trojaned app_process binary:

    echo -e '#!/system/bin/sh\nexport PATH=/system/bin:$PATH\ntouch
/data/trojan.out\nexec $0 "$@"' > app_process ; chmod 755 app_process
    PATH=`pwd`:$PATH su -c 'true'

The PATH vulnerability is being tracked under CVE-2013-6768.

 - Other environment variables could be used to affect the behavior of
the (moderately complex) subprocesses.  For instance, manipulation of
BOOTCLASSPATH could cause a malicious .jar file to be loaded into the
privileged Dalvik VM instance.  All three Superuser implementations
allowed Dalvik's BOOTCLASSPATH to be supplied by the attacker.

The BOOTCLASSPATH vulnerability is being tracked under CVE-2013-6774.

- 漏洞信息

ClockWorkMod Superuser Package for Android /system/xbin/su PATH Environment Variable Subversion Local Privilege Escalation
Local Access Required Misconfiguration
Loss of Integrity Solution Unknown
Exploit Public Uncoordinated Disclosure

- 漏洞描述

ClockWorkMod Superuser Package for Android is prone to a flaw in the way it loads the /system/xbin/su PATH environment variable. The program uses a fixed path to look for specific files or libraries. This path includes directories that may not be trusted or under user control. By placing a custom version of the file or library in the path, the program will load it before the legitimate version. This allows a local attacker to inject custom code that will be run with the privilege of the program or user executing the program. This attack can be leveraged remotely in some cases by placing the malicious file or library on a network share or extracted archive downloaded from a remote source. This can be done by tricking a user into opening an unspecified file from the local file system or a USB drive in some cases. This attack scenario is certainly possible, but rare.

- 时间线

2013-11-13 Unknow
2013-11-13 Unknow

- 解决方案

OSVDB is not currently aware of a solution for this vulnerability.

- 相关参考

- 漏洞作者

Unknown or Incomplete

- 漏洞信息

ClockWorkMod Superuser Package Environment Search Path Local Privilege Escalation Vulnerability
Environment Error 63710
No Yes
2013-11-13 12:00:00 2013-11-13 12:00:00
Kevin Cernekee

- 受影响的程序版本

- 漏洞讨论

ClockWorkMod Superuser package is prone to an local privilege-escalation vulnerability.

Attackers can leverage this issue to run commands with root privileges and gain escalated privileges.

ClockWorkMod Superuser is vulnerable; other versions may also be affected.

- 漏洞利用

Attackers can use standard commands to exploit this issue.

- 解决方案

Currently, we are not aware of any vendor-supplied patches. If you feel we are in error or are aware of more recent information, please mail us at:

- 相关参考