Vulnerabilities > CVE-2010-2693 - Permissions, Privileges, and Access Controls vulnerability in Freebsd

047910
CVSS 7.2 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
local
low complexity
freebsd
CWE-264
exploit available

Summary

FreeBSD 7.1 through 8.1-PRERELEASE does not copy the read-only flag when creating a duplicate mbuf buffer reference, which allows local users to cause a denial of service (system file corruption) and gain privileges via the sendfile system call.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Accessing, Modifying or Executing Executable Files
    An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
  • Leverage Executable Code in Non-Executable Files
    An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high. The attack can be directed at a client system, such as causing buffer overrun through loading seemingly benign image files, as in Microsoft Security Bulletin MS04-028 where specially crafted JPEG files could cause a buffer overrun once loaded into the browser. Another example targets clients reading pdf files. In this case the attacker simply appends javascript to the end of a legitimate url for a pdf (http://www.gnucitizen.org/blog/danger-danger-danger/) http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_here The client assumes that they are reading a pdf, but the attacker has modified the resource and loaded executable javascript into the client's browser process. The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality. The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
  • Blue Boxing
    This type of attack against older telephone switches and trunks has been around for decades. A tone is sent by an adversary to impersonate a supervisor signal which has the effect of rerouting or usurping command of the line. While the US infrastructure proper may not contain widespread vulnerabilities to this type of attack, many companies are connected globally through call centers and business process outsourcing. These international systems may be operated in countries which have not upgraded Telco infrastructure and so are vulnerable to Blue boxing. Blue boxing is a result of failure on the part of the system to enforce strong authorization for administrative functions. While the infrastructure is different than standard current applications like web applications, there are historical lessons to be learned to upgrade the access control for administrative functions.
  • Restful Privilege Elevation
    Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.
  • Target Programs with Elevated Privileges
    This attack targets programs running with elevated privileges. The attacker would try to leverage a bug in the running program and get arbitrary code to execute with elevated privileges. For instance an attacker would look for programs that write to the system directories or registry keys (such as HKLM, which stores a number of critical Windows environment variables). These programs are typically running with elevated privileges and have usually not been designed with security in mind. Such programs are excellent exploit targets because they yield lots of power when they break. The malicious user try to execute its code at the same level as a privileged system call.

Exploit-Db

descriptionFreeBSD mbufs() sendfile Cache Poisoning Privilege Escalation. CVE-2010-2693. Local exploit for freebsd platform
idEDB-ID:14688
last seen2016-02-01
modified2010-08-19
published2010-08-19
reporterkingcope
sourcehttps://www.exploit-db.com/download/14688/
titleFreeBSD - mbufs sendfile Cache Poisoning Privilege Escalation

Seebug

bulletinFamilyexploit
descriptionBUGTRAQ ID: 41577 CVE ID: CVE-2010-2693 FreeBSD就是一种运行在Intel平台上、可以自由使用的开放源码Unix类系统。 mbuf是FreeBSD内核进程间通讯和联网子系统中的基础内存管理单元。网络报文和套接字缓冲区依赖于mbuf进行存储。 在复制mbuf缓冲区引用时没有正确地拷贝只读标志,如果使用sendfile(2)系统调用在回环接口上传输数据,就可能导致修改所传送数据的后端内存页,造成数据破坏。本地攻击者可以通过精心控制系统文件的破坏情况来利用这种数据破坏提升权限。请注意攻击者可以破坏任意可读访问的文件。 FreeBSD FreeBSD 8.1 FreeBSD FreeBSD 8.0 FreeBSD FreeBSD 7.3 FreeBSD FreeBSD 7.1 厂商补丁: FreeBSD ------- FreeBSD已经为此发布了一个安全公告(FreeBSD-SA-10:07)以及相应补丁: FreeBSD-SA-10:07:Lost mbuf flag resulting in data corruption 链接:http://security.freebsd.org/advisories/FreeBSD-SA-10:07.mbuf.asc 补丁下载: 执行以下步骤之一; 1) 将有漏洞的系统升级到7-STABLE或8-STABLE,,或修改日期之后的RELENG_8_1、RELENG_8_0、RELENG_7_3或 RELENG_7_1安全版本。 2) 如果要通过源码路径升级有漏洞的系统: 以下补丁确认可应用于FreeBSD 7.1、7.3、8.0和8.1系统。 a) 从以下位置下载相关补丁,并使用PGP工具验证附带的PGP签名。 # fetch http://security.FreeBSD.org/patches/SA-10:07/mbuf.patch # fetch http://security.FreeBSD.org/patches/SA-10:07/mbuf.patch.asc b) 以root执行以下命令: # cd /usr/src # patch < /path/to/patch c) 如<URL:http://www.FreeBSD.org/handbook/kernelconfig.html> 所述重新编译内核并重启系统。
idSSV:19970
last seen2017-11-19
modified2010-07-20
published2010-07-20
reporterRoot
titleFreeBSD mbuf本地权限提升漏洞