CVE-2026-33429: Parse Server LiveQuery Protected Field Change Detection Oracle
Summary
CVE-2026-33429: Parse Server has a protected field change detection oracle via LiveQuery watch parameter. Affects parse-server across 2 version ranges.
< 8.6.54
>= 9.0.0, < 9.6.0-alpha.43
Fixed in 8.6.54 or 9.6.0-alpha.43, depending on the release line you run. How to fix ↓
Also tracked for
- parse · Bitnami
The same CVE-2026-33429 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
Parse Server is an open-source backend platform that enables developers to build applications with a robust server-side infrastructure. It provides features such as data storage, user management, and real-time capabilities through LiveQuery. However, it has a vulnerability that allows attackers to exploit the LiveQuery functionality to detect changes in protected fields, potentially exposing sensitive information.
Vulnerability Detail
The vulnerability arises from the ability of an attacker to subscribe to LiveQuery with a 'watch' parameter that targets a protected field. Although the actual value of the protected field is not included in event payloads, the presence or absence of update events can indicate whether the protected field has changed. This creates a binary oracle, allowing attackers to infer the value of boolean protected fields based on the timing of change events. The vulnerability is classified under CWE-203, which pertains to information exposure through an error message.
How To Fix
Latest published version: 9.10.5 as of 22 Oct 2026
npm install parse-server@9.10.5Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
< 8.6.548.6.54npm install parse-server@8.6.54 -
>= 9.0.0, < 9.6.0-alpha.439.6.0-alpha.43npm install parse-server@9.6.0-alpha.43
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Workaround
There are no known workarounds for this vulnerability. It is recommended to apply the patch as soon as possible to mitigate the risk.
Conclusion
The CVE-2026-33429 vulnerability in Parse Server poses a significant risk by allowing attackers to infer changes in protected fields through LiveQuery. It is crucial for developers to update to the patched versions to safeguard their applications against potential data exposure.
See every vulnerability recorded for parse-server →
FAQ
The vulnerability allows attackers to detect changes in protected fields through LiveQuery subscriptions, potentially exposing sensitive information.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in your software. Check your application against the vulnerability using the Vulert playground at Vulert Scanner.
Versions 9.0.0 to 9.6.0-alpha.42 and 0 to 8.6.53 of Parse Server are affected by this vulnerability.
Yes, the vulnerability can lead to the exposure of sensitive information if an attacker can infer the values of protected fields.
It is highly recommended to prioritize updating to the patched version as there are no effective workarounds for this vulnerability.
References
Related vulnerabilities
Recent vulnerabilities recorded for parse-server.
