Vulnerability in Parse-Community Parse-Server

CVE-2026-33429

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.54 and 9.6.0-alpha.43, an attacker can subscribe to LiveQuery with a watch parameter targeting a protected field. Although the protected field value is properly stripped from event payloads, the presence or absence of update events reveals whether the protected field changed, creating a binary oracle. For boolean protected fields, the timing of change events is equivalent to knowing the field value. This issue has been patched in versions 8.6.54 and 9.6.0-alpha.43.

EPSS: 0.003 (24.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33429?
CVE-2026-33429 is a medium-severity vulnerability in Parse-Community Parse-Server, classified under Observable Discrepancy. CVSS score: 5.3/10. Published 2026-03-24.
How severe is CVE-2026-33429?
Medium severity. CVSS v3 base score is 5.3 out of 10.