Vulnerability · Published Mar 31, 2026 · Assigned by GitHub_M
CVE-2026-34532Parse Server: Cloud function validator bypass via prototype chain traversal
Critical 9.1
In plain English
A critical-severity incorrect authorization in parse-server from parse-community. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | parse-server | 9.7.0-alpha.11 | GHSA-vpj2-qq7w-5qq6 |
| npm | parse-server | 8.6.67 | GHSA-vpj2-qq7w-5qq6 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| parse-community | parse-server | < 8.6.67>= 9.0.0, < 9.7.0-alpha.11 |
Weakness: CWE-863 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/parse-community/parse-server/security/advisories/GHSA-vpj2-qq7w-5qq6 x_refsource_CONFIRM
- https://github.com/parse-community/parse-server/pull/10342 x_refsource_MISC
- https://github.com/parse-community/parse-server/pull/10343 x_refsource_MISC
- https://github.com/parse-community/parse-server/commit/4fc48cf28f22eea200d74d883505f485234a48d7 x_refsource_MISC
- https://github.com/parse-community/parse-server/commit/dc59e272665644083c5b7f6862d88ce1ef0b2674 x_refsource_MISC