Vulnerabilities > CVE-2008-3531 - Buffer Errors vulnerability in Freebsd 7.0/7.1
Attack vector
LOCAL Attack complexity
MEDIUM Privileges required
NONE Confidentiality impact
COMPLETE Integrity impact
COMPLETE Availability impact
COMPLETE Summary
Stack-based buffer overflow in sys/kern/vfs_mount.c in the kernel in FreeBSD 7.0 and 7.1, when vfs.usermount is enabled, allows local users to gain privileges via a crafted (1) mount or (2) nmount system call, related to copying of "user defined data" in "certain error conditions."
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| OS | 2 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Buffer Overflow via Environment Variables This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
- Overflow Buffers Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
- Client-side Injection-induced Buffer Overflow This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
- Filter Failure through Buffer Overflow In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
- MIME Conversion An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
Exploit-Db
| description | FreeBSD 7.0/7.1 vfs.usermount Local Privilege Escalation Exploit. CVE-2008-3531. Local exploit for freebsd platform |
| id | EDB-ID:9082 |
| last seen | 2016-02-01 |
| modified | 2009-07-09 |
| published | 2009-07-09 |
| reporter | Patroklos Argyroudis |
| source | https://www.exploit-db.com/download/9082/ |
| title | FreeBSD 7.0/7.1 vfs.usermount - Local Privilege Escalation Exploit |
Seebug
bulletinFamily exploit description No description provided by source. id SSV:11781 last seen 2017-11-19 modified 2009-07-10 published 2009-07-10 reporter Root source https://www.seebug.org/vuldb/ssvid-11781 title FreeBSD 7.0/7.1 vfs.usermount Local Privilege Escalation Exploit bulletinFamily exploit description BUGTRAQ ID: 31002 CVE ID：CVE-2008-3531 CNCVE ID：CNCVE-20083531 FreeBSD是一款开放源代码的操作系统。 FreeBSD处理mount(2)和nmount(2)系统调用存在问题，本地攻击者可以利用漏洞以内核进程权限执行任意指令。 各种用户定义的输入如挂接点，设备，挂接选项会作为参数传递给nmount(2)到内核，在部分错误条件下，用户定义的数据会没有充分边界检查的情况下拷贝到存储在内核中的堆栈缓冲区中。如果系统配置成允许非特权用户挂接文件系统，可导致这些非特权用户通过设置vfs.usermount sysctl(8)变量利用这些系统调用，以内核进程权限执行任意指令。 FreeBSD FreeBSD 7.0-STABLE FreeBSD FreeBSD 7.0-RELEASE 厂商解决方案 供应商提供如下补丁及解决方法： 1）更新受影响系统到7-STABLE，或者到更正日期之后的RELENG_7_0,安全版本。 2）为当前系统打补丁： 如下补丁经验证可应用于FreeBSD 7.0系统。 a)从如下位置下载相关补丁，并使用PGP工具验证附带的PGP签名： # fetch <a href=http://security.FreeBSD.org/patches/SA-08:08/nmount.patch target=_blank>http://security.FreeBSD.org/patches/SA-08:08/nmount.patch</a> # fetch <a href=http://security.FreeBSD.org/patches/SA-08:08/nmount.patch.asc target=_blank>http://security.FreeBSD.org/patches/SA-08:08/nmount.patch.asc</a> b)应用补丁 # cd /usr/src # patch < /path/to/patch c)如<<a href=http://www.freebsd.org/handbook/kernelconfig.html> target=_blank>http://www.freebsd.org/handbook/kernelconfig.html></a> 所述重新编译操作系统并重启系统。 id SSV:3982 last seen 2017-11-19 modified 2008-09-10 published 2008-09-10 reporter Root title FreeBSD 'mount(2)'和'nmount(2)'多个栈缓冲区溢出漏洞