CVE-2026-34532

CRITICAL

Parse Server: Cloud function validator bypass via prototype chain traversal

Title source: cna

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-alpha.11, 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-alpha.11.

Scores

CVSS v3 9.1
EPSS 0.0004
EPSS Percentile 11.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-863
Status published
Products (5)
npm/parse-server 9.0.0 - 9.7.0-alpha.11npm
parse-community/parse-server < 8.6.67
parse-community/parse-server >= 9.0.0, < 9.7.0-alpha.11
parseplatform/parse-server 9.7.0 alpha1 (10 CPE variants)
parseplatform/parse-server < 8.6.67
Published Mar 31, 2026
Tracked Since Mar 31, 2026