CVE-2021-39138

New anonymous user session acts as if it's created with password

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Developers can use the REST API to signup users and also allow users to login anonymously. Prior to version 4.5.1, when an anonymous user is first signed up using REST, the server creates session incorrectly. Particularly, the `authProvider` field in `_Session` class under `createdWith` shows the user logged in creating a password. If a developer later depends on the `createdWith` field to provide a different level of access between a password user and anonymous user, the server incorrectly classified the session type as being created with a `password`. The server does not currently use `createdWith` to make decisions about internal functions, so if a developer is not using `createdWith` directly, they are not affected. The vulnerability only affects users who depend on `createdWith` by using it directly. The issue is patched in Parse Server version 4.5.1. As a workaround, do not use the `createdWith` Session field to make decisions if one allows anonymous login.

Categories

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: parse-community parse-server
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-39138?
CVE-2021-39138 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39138?
To fix CVE-2021-39138, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39138 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39138 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39138?
CVE-2021-39138 affects parse-community parse-server.
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