CVE-2026-32886: Parse Server's Cloud function dispatch crashes server via prototype chain traversal

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-18 · updated 2026-06-17
Weakness: CWE-1321

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0-alpha.24 and 8.6.47, remote clients can crash the Parse Server process by calling a cloud function endpoint with a crafted function name that traverses the JavaScript prototype chain of a registered cloud function handler, causing a stack overflow. The fix in versions 9.6.0-alpha.24 and 8.6.47 restricts property lookups during cloud function name resolution to own properties only, preventing prototype chain traversal from stored function handlers. There is no known workaround.

Affected products

parse-community parse-server: before 8.6.47; from 9.0.0 before 9.6.0; 9.6.0-alpha1, 9.6.0-alpha10, 9.6.0-alpha11, 9.6.0-alpha12, 9.6.0-alpha13, 9.6.0-alpha14 (+17) — fixed in 8.6.47, 9.6.0

How to fix

Upgrade to a fixed version: parse-community parse-server 8.6.47, 9.6.0. Check the vendor advisory for mitigations.

References

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