Use After Free in MongoDB
CVE-2026-18711
An issue in MongoDB Server's query execution engine could allow an authenticated user with read and write privileges to cause an internal reference to be used after the underlying memory has been freed, when running certain queries against time-series collections. This could result in a server crash or disclosure of freed memory contents within query results.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (38.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 38.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- MongoDB — versions 9.0.0, 9.1.0
- MongoDB Server — versions 8.3.0, 8.0
Weakness classification (CWE)
References
- jira.mongodb.org/browse/SERVER-130247 (Patch, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-18711?
- CVE-2026-18711 is a high-severity vulnerability in MongoDB, classified under Use After Free. CVSS score: 7.1/10. Published 2026-08-11.
- How severe is CVE-2026-18711?
- High severity. CVSS v3 base score is 7.1 out of 10.