CVE-2026-34363
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk29th percentile - higher than 29% of all known CVEs
Summary
Parse Server before versions 8.6.65 and 9.7.0-alpha.9 has a LiveQuery vulnerability. When multiple clients subscribe to the same class, shared mutable objects modified by sensitive data filters can leak protected fields or authentication data to unauthorized clients. Also, afterEvent Cloud Code trigger modifications can leak to other subscribers.
Risk Assessment
An attacker can access protected data or authentication credentials of other users, compromising data confidentiality and integrity.
Recommendation
Update Parse Server to version 8.6.65 or later (for 8.x branch) or 9.7.0-alpha.9 or later (for 9.x branch).
Original NVD description (English source)
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.