CVE-2026-34363

The record

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.65 and 9.7.0-alpha.9, when multiple clients subscribe to the same class via LiveQuery, the event handlers process each subscriber concurrently using shared mutable objects. The sensitive data filter modifies these shared objects in-place, so when one subscriber's filter removes a protected field, subsequent subscribers may receive the already-filtered object. This can cause protected fields and authentication data to leak to clients that should not see them, or cause clients that should see the data to receive an incomplete object. Additionally, when an afterEvent Cloud Code trigger is registered, one subscriber's trigger modifications can leak to other subscribers through the same shared mutable state. Any Parse Server deployment using LiveQuery with protected fields or afterEvent triggers is affected when multiple clients subscribe to the same class. This issue has been patched in versions 8.6.65 and 9.7.0-alpha.9.

Affected packages

Related vulnerabilities

• GHSA-m983-v2ff-wq65 LiveQuery protected field leak via shared mutable state across concurrent subscribers Same vulnerability
• GHSA-97pr-9hgg-3p8r parse-server: LiveQuery discloses object data to a subscriber across an ACL read-access… Also affects parse-server
• GHSA-wmwx-jr2p-4j4r parse-server: Relation `$relatedTo` query bypasses `protectedFields` and owning-object ACL Also affects parse-server
• GHSA-7wqv-xjf3-x35v parse-server: Stored XSS via trailing-dot filename bypassing file upload extension… Also affects parse-server
• GHSA-p84r-h6rx-f2xr parse-server: Server option routeAllowList is bypassable through batch sub-requests Also affects parse-server
• GHSA-cgxm-vr2f-6fj8 parse-server: Denial of service via exponential-time processing of deeply nested query… Also affects parse-server
• CVE-2026-53726 Parse Server is an open source backend that can be deployed to any infrastructure that… Also affects parse-server
• CVE-2026-53724 Parse Server is an open source backend that can be deployed to any infrastructure that… Also affects parse-server