CVE-2026-34595

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.70 and 9.7.0, an authenticated user with find class-level permission can bypass the protectedFields class-level permission setting on LiveQuery subscriptions. By sending a subscription with a $or, $and, or $nor operator value as a plain object with numeric keys and a length property (an "array-like" object) instead of an array, the protected-field guard is bypassed. The subscription event firing acts as a binary oracle, allowing the attacker to infer whether a protected field matches a given test value. This issue has been patched in versions 8.6.70 and 9.7.0.

How to fix CVE-2026-34595

To remediate CVE-2026-34595, upgrade the affected package to a fixed version below.

• —upgrade to 8.6.70 or later
• —upgrade to 9.7.0-alpha.16 or later

Is CVE-2026-34595 being exploited?

Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 8.6.70, >= 9.0.0, < 9.7.0
• >= 9.0.0, < 9.7.0-alpha.16

CVSS scores

References (7)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2026-34595
• PATCHgithub.com/parse-community/parse-server
• WEBgithub.com/parse-community/parse-server/commit/f63fd1a3fe0a7c1c5fe809f01b0e04759e8c9b98
• WEBgithub.com/parse-community/parse-server/commit/ffad0ec6b971ee0dd9545e1bf1fb34ddebf275c2