Use After Free in MongoDB
CVE-2026-18692
An issue in MongoDB Server's handling of timeseries bucket lifecycle could allow an authenticated user with write privileges to cause an internal reference to be used after the underlying memory has been freed. Subsequent operations could then result in a server crash or, potentially, execution of unintended code.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (45.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.001
Affected products
- MongoDB — versions 9.0.0, 9.1.0
- MongoDB Server — versions 8.3.0
Weakness classification (CWE)
References
- jira.mongodb.org/browse/SERVER-129887 (Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-18692?
- CVE-2026-18692 is a high-severity vulnerability in MongoDB, classified under Use After Free. CVSS score: 8.8/10. Published 2026-08-11.
- How severe is CVE-2026-18692?
- High severity. CVSS v3 base score is 8.8 out of 10.