Vulnerabilities > CVE-2023-32689 - Unrestricted Upload of File with Dangerous Type vulnerability in Parseplatform Parse-Server
Summary
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Versions prior to 5.4.4 and 6.1.1 are vulnerable to a phishing attack vulnerability that involves a user uploading malicious files. A malicious user could upload an HTML file to Parse Server via its public API. That HTML file would then be accessible at the internet domain at which Parse Server is hosted. The URL of the the uploaded HTML could be shared for phishing attacks. The HTML page may seem legitimate because it is served under the internet domain where Parse Server is hosted, which may be the same as a company's official website domain. An additional security issue arises when the Parse JavaScript SDK is used. The SDK stores sessions in the internet browser's local storage, which usually restricts data access depending on the internet domain. A malicious HTML file could contain a script that retrieves the user's session token from local storage and then share it with the attacker. The fix included in versions 5.4.4 and 6.1.1 adds a new Parse Server option `fileUpload.fileExtensions` to restrict file upload on Parse Server by file extension. It is recommended to restrict file upload for HTML file extensions, which this fix disables by default. If an app requires upload of files with HTML file extensions, the option can be set to `['.*']` or another custom value to override the default.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Accessing Functionality Not Properly Constrained by ACLs In applications, particularly web applications, access to functionality is mitigated by the authorization framework, whose job it is to map ACLs to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application or can run queries for data that he is otherwise not supposed to.
- Privilege Abuse An adversary is able to exploit features of the target that should be reserved for privileged users or administrators but are exposed to use by lower or non-privileged accounts. Access to sensitive information and functionality must be controlled to ensure that only authorized users are able to access these resources. If access control mechanisms are absent or misconfigured, a user may be able to access resources that are intended only for higher level users. An adversary may be able to exploit this to utilize a less trusted account to gain information and perform activities reserved for more trusted accounts. This attack differs from privilege escalation and other privilege stealing attacks in that the adversary never actually escalates their privileges but instead is able to use a lesser degree of privilege to access resources that should be (but are not) reserved for higher privilege accounts. Likewise, the adversary does not exploit trust or subvert systems - all control functionality is working as configured but the configuration does not adequately protect sensitive resources at an appropriate level.
References
- https://github.com/parse-community/parse-server/pull/8537
- https://github.com/parse-community/parse-server/pull/8538
- https://github.com/parse-community/parse-server/security/advisories/GHSA-9prm-jqwx-45x9
- https://github.com/parse-community/parse-server/pull/8537
- https://github.com/parse-community/parse-server/security/advisories/GHSA-9prm-jqwx-45x9
- https://github.com/parse-community/parse-server/pull/8538