CVE-2026-34532

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.67 and 9.7.0, an attacker can bypass Cloud Function validator access controls by appending "prototype.constructor" to the function name in the URL. When a Cloud Function handler is declared using the function keyword and its validator is a plain object or arrow function, the trigger store traversal resolves the handler through its own prototype chain while the validator store fails to mirror this traversal, causing all access control enforcement to be skipped. This allows unauthenticated callers to invoke Cloud Functions that are meant to be protected by validators such as requireUser, requireMaster, or custom validation logic. This issue has been patched in versions 8.6.67 and 9.7.0.

How to fix CVE-2026-34532

To remediate CVE-2026-34532, upgrade the affected package to a fixed version below.

• —upgrade to 8.6.67 or later
• —upgrade to 9.7.0-alpha.11 or later

Is CVE-2026-34532 being exploited?

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

Affected packages (2)

• from 0, < 8.6.67, >= 9.0.0, < 9.7.0
• >= 9.0.0, < 9.7.0-alpha.11

CVSS scores

References (7)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2026-34532
• PATCHgithub.com/parse-community/parse-server
• WEBgithub.com/parse-community/parse-server/commit/4fc48cf28f22eea200d74d883505f485234a48d7
• WEBgithub.com/parse-community/parse-server/commit/dc59e272665644083c5b7f6862d88ce1ef0b2674