What is CVE-2026-120819?

CVE-2026-120819 is a medium-severity vulnerability in MongoDB Server, classified under Use After Free. CVSS score: 4.3/10. Published 2026-11-10.

How severe is CVE-2026-120819?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Use After Free in MongoDB Server

CVE-2026-120819

A memory-management flaw in the server-side JavaScript execution component of MongoDB Server can allow an authenticated user holding only read privileges to cause the server to access memory that has already been released. By submitting a specially crafted database command that runs user-supplied JavaScript, the user can cause a bounded amount of adjacent process memory to be returned in the command's result. This results in the user obtaining information they are not authorized to access. Integrity and availability are not affected.

Vulnerability class: Use-After-Free

Published 2026-11-10 · last modified 2026-11-10.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

MongoDB Server

Weakness classification (CWE)

CWE-416 — Use After Free

References

jira.mongodb.org/browse/SERVER-134893

Frequently asked questions

What is CVE-2026-120819?: CVE-2026-120819 is a medium-severity vulnerability in MongoDB Server, classified under Use After Free. CVSS score: 4.3/10. Published 2026-11-10.
How severe is CVE-2026-120819?: Medium severity. CVSS v3 base score is 4.3 out of 10.