CVE-2026-33409
Parse Server has an auth provider validation bypass on login via partial authData
Impact
### Impact An authentication bypass vulnerability allows an attacker to log in as any user who has linked a third-party authentication provider, without knowing the user's credentials. The attacker only needs to know the user's provider ID to gain full access to their account, including a valid session token. This affects Parse Server deployments where the server option `allowExpiredAuthDataToken` is set to `true`. The default value is `false`. ### Patches Auth providers are now always validated on login, regardless of the `allowExpiredAuthDataToken` setting. The option `allowExpiredAuthDataToken` has been deprecated and will be removed in a future major version. ### Workarounds Set `allowExpiredAuthDataToken` to `false` (the default) or remove the option from the server configuration.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | parse-server | >= 9.0.0, < 9.6.0-alpha.41 | 9.6.0-alpha.41 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Parseplatform | Parse-Server | before 8.6.52 from 9.0.0 before 9.6.0 Version 9.6.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/parse-community/parse-server/commit/8d7df5639c4a35768fe8b78b4580b30e8a74721c
- https://github.com/parse-community/parse-server/commit/98f4ba5bcf2c199bfe6225f672e8edcd08ba732d
- https://github.com/parse-community/parse-server/pull/10246
- https://github.com/parse-community/parse-server/pull/10247
- https://github.com/parse-community/parse-server/security/advisories/GHSA-pfj7-wv7c-22pr
- https://github.com/advisories/GHSA-pfj7-wv7c-22pr
- https://nvd.nist.gov/vuln/detail/CVE-2026-33409