# CVE-2026-121965: Parse Server prototype pollution in Cloud Code and LiveQuery

Source: https://junglewise.ai/threats/cve-2026-121965-parse-server-before-8-6-113-and-9-0-0-before-9-10-6-alpha-5  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-04. Updated: 2026-11-04  
License: CC BY 4.0 with a link back

CVE-2026-121965 · Severity: medium · CVSS 5.3 · Published 2026-11-04

Parse Server is a backend-as-a-service platform that powers cloud applications and handles data storage. A prototype pollution vulnerability allows attackers with write access to corrupt shared built-in functions, causing unrelated requests to fail and denying service to all applications until the server is restarted. This can impact availability across all hosted applications on the affected server.

Technologies: [Parse Community Parse Server](https://junglewise.ai/threats/technologies/parse-community-parse-server). Vendors: [Parse Community](https://junglewise.ai/threats/vendors/parse-community).

## Quick answers

**Is CVE-2026-121965 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121965 being exploited in the wild.

**How severe is CVE-2026-121965?** Medium severity, with a CVSS score of 5.3, published 4 November 2026.

**Which products and versions are affected?** Parse Community Parse Server before 8.6.113 and 9.0.0 before 9.10.6-alpha.5.

**Is there a fix for CVE-2026-121965?** Yes: fixed in Parse Server 8.6.113, 9.10.6-alpha.5. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-121965 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-121965?** Check whether you run Parse Community Parse Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in Parse Server 8.6.113, 9.10.6-alpha.5

## Technical details

The vulnerability is a prototype pollution flaw in object building for Cloud Code triggers and LiveQuery. When a dot notation key with an intermediate segment resolves through an inherited member, it writes onto a process-wide built-in object. Attackers must have write access to an object in a class with a trigger or LiveQuery enabled; the fix prevents this by properly validating and sanitizing dot notation keys during object construction.

## Affected products

- Parse Community Parse Server before 8.6.113 and 9.0.0 before 9.10.6-alpha.5

## Timeline

- 2026-11-04: disclosed
- 2026-10-20: patched

## References

- [https://github.com/parse-community/parse-server/pull/10810](https://github.com/parse-community/parse-server/pull/10810)
- [https://github.com/parse-community/parse-server/pull/10811](https://github.com/parse-community/parse-server/pull/10811)

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