Use After Free in MongoDB

CVE-2026-18700

An issue in MongoDB Server's geospatial validation could allow an authenticated user with write privileges to cause an internal reference to be used after the underlying memory has been freed, through concurrent operations against a collection using a certain type of validator. This could result in a server crash, leading to a denial of service.

Vulnerability class: Use-After-Free

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.004 (31.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 31.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-18700: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-18700?
CVE-2026-18700 is a medium-severity vulnerability in MongoDB, classified under Use After Free. CVSS score: 6.5/10. Published 2026-08-11.
How severe is CVE-2026-18700?
Medium severity. CVSS v3 base score is 6.5 out of 10.