CVE-2026-34363

MEDIUM

Parse Server: LiveQuery protected field leak via shared mutable state across concurrent subscribers

Title source: cna

Description

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.

Scores

CVSS v3 5.3
EPSS 0.0006
EPSS Percentile 17.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-362
Status published
Products (5)
npm/parse-server 9.0.0 - 9.7.0-alpha.9npm
parse-community/parse-server < 8.6.65
parse-community/parse-server >= 9.0.0, < 9.7.0-alpha.9
parseplatform/parse-server 9.7.0 alpha1 (8 CPE variants)
parseplatform/parse-server < 8.6.65
Published Mar 31, 2026
Tracked Since Mar 31, 2026