Auth bypass in Parse-Community Parse-Server
CVE-2026-33421
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.53 and 9.6.0-alpha.42, Parse Server's LiveQuery WebSocket interface does not enforce Class-Level Permission (CLP) pointer permissions (readUserFields and pointerFields). Any authenticated user can subscribe to LiveQuery events and receive real-time updates for all objects in classes protected by pointer permissions, regardless of whether the pointer fields on those objects point to the subscribing user. This bypasses the intended read access control, allowing unauthorized access to potentially sensitive data that is correctly restricted via the REST API. This issue has been patched in versions 8.6.53 and 9.6.0-alpha.42.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (36.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000
Affected products
- Parse-Community Parse-Server — versions < 8.6.53, >= 9.0.0, < 9.6.0-alpha.42
- Parseplatform Parse-Server — versions 9.6.0
Weakness classification (CWE)
References
- github.com/parse-community/parse-server/security/advisories/GHSA-fph2-r4qg-9576 (Vendor Advisory)
- github.com/parse-community/parse-server/pull/10250 (Issue Tracking)
- github.com/parse-community/parse-server/pull/10252 (Issue Tracking)
- github.com/parse-community/parse-server/commit/6c3317aca6eb618ac48f999021ae3ef7… (Patch)
- github.com/parse-community/parse-server/commit/976dad109f3fe3fbd0a3a35ef62e7a5d… (Patch)
Frequently asked questions
- What is CVE-2026-33421?
- CVE-2026-33421 is a medium-severity vulnerability in Parse-Community Parse-Server, classified under Incorrect Authorization. CVSS score: 6.5/10. Published 2026-03-24.
- How severe is CVE-2026-33421?
- Medium severity. CVSS v3 base score is 6.5 out of 10.