CVE-2021-39138
mediumpriority · track · 26OT risk · elevatedEPSS 0.010 · 62 %ileEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
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affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-23r4-5mxp-c7g5parse-server new anonymous user session acts as if it's created with password2021-08-23ghsa · osvUS
### 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
- BIT-parse-2021-39138New anonymous user session acts as if it's created with password2024-03-06vendor · osvUS
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.
also known as (5)
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sources
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references (11)
External citations — patches, advisories, analysis.
- https://github.com/parse-community/parse-server/commit/147bd9a3dc43391e92c36e05d5db860b04ca27dbcnnvd
- https://github.com/parse-community/parse-server/releases/tag/4.5.1cnnvd
- https://github.com/parse-community/parse-server/security/advisories/GHSA-23r4-5mxp-c7g5cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-39138cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021082712cnnvd
- https://github.com/parse-community/parse-server/commit/147bd9a3dc43391e92c36e05d5db860b04ca27dbenisa_euvd
- https://github.com/parse-community/parse-server/releases/tag/4.5.1enisa_euvd
- https://github.com/parse-community/parse-server/security/advisories/GHSA-23r4-5mxp-c7g5enisa_euvd
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