# CVE-2026-18693: Out-of-Bounds Read/Write in MongoDB Timeseries Bucket Handling Leads to Denial of Service and Potential Memory Disclosure

> CVE-2026-18693: Out-of-Bounds Read/Write in MongoDB Timeseries Bucket Handling Leads to Denial of Service and Potential Memory Disclosure. CVSS 7.6 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-18693
Last updated: 2026-10-23T21:10:00Z

- Published: 2026-08-11 18:38 UTC · Updated: 2026-10-23 21:10 UTC · Assigner: mongodb
- CVSS: 7.6 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
- EPSS: 0.34%, 27th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-787

## Description

An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.

## Affected vendors and products

- MongoDB: MongoDB Server

## Tracked companies

- [MongoDB Atlas](https://rewindex.com/company/mongodb-atlas.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-18693)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-18693)
- [https://jira.mongodb.org/browse/SERVER-129994](https://jira.mongodb.org/browse/SERVER-129994)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-18693 · Markdown: https://rewindex.com/cve/CVE-2026-18693.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-18693 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:09:24.352Z