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-alpha.18, 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-alpha.18.

References

• https://github.com/parse-community/parse-server/commit/f63fd1a3fe0a7c1c5fe809f01b0e04759e8c9b98
• https://github.com/parse-community/parse-server/commit/ffad0ec6b971ee0dd9545e1bf1fb34ddebf275c2
• https://github.com/parse-community/parse-server/pull/10350
• https://github.com/parse-community/parse-server/pull/10351
• https://github.com/parse-community/parse-server/security/advisories/GHSA-mmg8-87c5-jrc2