CVE-2021-39138

Description

### Impact Developers that use the REST API to signup users and also allow users to login anonymously. 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 currently doesn't use `createdWith` to make decisions on how things work internally, so if a developer isn't using `createdWith` directly, there's nothing to worry about. The vulnerability only affects users who depend on `createdWith` by using it directly. ### Patches Upgrade to version 4.5.1. ### Workarounds Don't use the `createdWith` Session field to make decisions if you allow anonymous login. ### References n/a

How to fix CVE-2021-39138

To remediate CVE-2021-39138, upgrade the affected package to a fixed version below.

• —upgrade to 4.5.1 or later
• —upgrade to 4.5.2 or later

Is CVE-2021-39138 being exploited?

Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 4.5.1
• from 0, < 4.5.2

CVSS scores

References (6)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-39138
• PATCHgithub.com/parse-community/parse-server
• WEBgithub.com/parse-community/parse-server/commit/147bd9a3dc43391e92c36e05d5db860b04ca27db
• WEBgithub.com/parse-community/parse-server/releases/tag/4.5.1