CVE-2021-39187

Name: CVE-2021-39187
Creator: NVD / NIST
Published: 2021-09-02T16:15:07.54+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.76%

Last modified Jun 17, 2026

CVE-2021-39187 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to version 4.10.3, Parse Server crashes when if a query request contains an invalid value for the `explain` option. EPSS estimates a 1.76% chance of exploitation in the next 30 days.

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to version 4.10.3, Parse Server crashes when if a query request contains an invalid value for the `explain` option. This is due to a bug in the MongoDB Node.js driver which throws an exception that Parse Server cannot catch. There is a patch for this issue in version 4.10.3. No workarounds aside from upgrading are known to exist.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.76%

75.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Parseplatform	Parse-Server	< 4.10.3

References

https://github.com/parse-community/parse-server/commit/308668c89474223e2448be92d6823b52c1c313ecPatch, Third Party Advisory
https://github.com/parse-community/parse-server/releases/tag/4.10.3Third Party Advisory
https://github.com/parse-community/parse-server/security/advisories/GHSA-xqp8-w826-hh6xThird Party Advisory
https://jira.mongodb.org/browse/NODE-3463Patch, Third Party Advisory
https://github.com/parse-community/parse-server/commit/308668c89474223e2448be92d6823b52c1c313ecPatch, Third Party Advisory
https://github.com/parse-community/parse-server/releases/tag/4.10.3Third Party Advisory
https://github.com/parse-community/parse-server/security/advisories/GHSA-xqp8-w826-hh6xThird Party Advisory
https://jira.mongodb.org/browse/NODE-3463Patch, Third Party Advisory

Timeline

Published: Sep 2, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39187?

How severe is CVE-2021-39187?

CVE-2021-39187 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.76% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39187?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-39187?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST