CVE-2022-44635 is a critical security vulnerability that affects Apache Fineract, a popular open-source software platform designed to help financial institutions manage their operations and customer relationships. A successful attack exploiting this vulnerability allows an authenticated user to perform remote code execution due to a path traversal vulnerability in a file upload component of Apache Fineract. This poses an immense threat to the confidentiality, integrity, and availability of the affected systems. The vulnerability affects Apache Fineract version 1.8. and prior versions, and users are urged to upgrade to version 1.8.1 immediately.

Vulnerability Details

An attacker targeting CVE-2022-44635 can potentially run arbitrary code on the victim's server, leading to the compromise of sensitive data, disruption of services, and even full system takeover. The vulnerability is caused by a path traversal issue in the file upload component of Apache Fineract. By exploiting this component, an attacker can upload malicious files to arbitrary locations on the server, resulting in remote code execution.

The following code snippet demonstrates the flawed file upload implementation

@RequestMapping(value = "/{clientId}/documents", method = RequestMethod.POST, consumes = { "multipart/form-data" })
public ResponseEntity<ApiGlobalErrorResponse> createDocument(@PathVariable("clientId") final Long resourceId,
                                                              @RequestParam("file") final MultipartFile inputFile) {

    String fileName = inputFile.getOriginalFilename();
    String fileExtension;

    if (fileName.contains("/")) {
        fileName = fileName.substring(fileName.lastIndexOf("/") + 1);
    }

As seen in the code snippet, the fileName variable accepts user input without proper sanitization, making it vulnerable to path traversal attacks. By manipulating the file path using special characters such as "../", an attacker can potentially upload files to unintended locations and subsequently gain code execution privileges.

Exploit

To successfully exploit this vulnerability, an attacker must first authenticate with the Apache Fineract server. After authentication, the attacker can craft a malicious request, injecting a specially crafted file name, as shown below:

POST /fineract-provider/api/v1/clients/1/documents HTTP/1.1
Host: example.com
Content-Type: multipart/form-data; boundary=---------------------------12345678123456
Content-Length: 251
token: <authentication_token>

-----------------------------12345678123456
Content-Disposition: form-data; name="file"; filename="../../webapps/ROOT/malicious.jsp"
Content-Type: application/octet-stream

<contents_of_malicious_jsp_file>
-----------------------------12345678123456--

Upon successful exploitation, the attacker can remotely execute the uploaded code and gain unauthorized access to the victim's system.

Remediation

Apache Fineract has addressed this vulnerability in version 1.8.1 by properly sanitizing the user input for the file upload functionality. Users are strongly recommended to upgrade to the latest version as soon as possible.

Original References

1. CVE-2022-44635: https://nvd.nist.gov/vuln/detail/CVE-2022-44635
2. Apache Fineract Security Advisory: https://fineract.apache.org/security.html
3. Apache Fineract GitHub Repository: https://github.com/apache/fineract

Conclusion

CVE-2022-44635 is a significant security risk that puts sensitive data and operational integrity at risk. Immediate action to upgrade to Apache Fineract version 1.8.1 is strongly recommended to mitigate this vulnerability and protect your organization. Always ensure that your software is up to date and follow best security practices to minimize your exposure to such vulnerabilities.

Timeline

Published on: 11/29/2022 15:15:00 UTC
Last modified on: 12/01/2022 21:24:00 UTC