# CVE-2026-72678: Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service

> CVE-2026-72678: Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-72678
Last updated: 2026-09-01T15:28:17Z

- Published: 2026-08-13 19:11 UTC · Updated: 2026-09-01 15:28 UTC · Assigner: elastic
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.47%, 41th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-789

## Description

Elasticsearch does not validate a size value taken from a user-supplied input before that value is used to reserve memory for an internal data structure. An authenticated user holding only read privileges can submit a single small crafted request to a product API endpoint that causes the node to attempt an excessively large allocation. The resulting memory exhaustion raises a fatal error that terminates the Elasticsearch node process, causing a denial of service for the affected node and degrading cluster health. The defect is not volumetric, so a single request is sufficient regardless of the heap size configured on the target node.

## Affected vendors and products

- Elastic: Elasticsearch

## Tracked companies

- [Elastic Cloud](https://rewindex.com/company/elastic-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-72678)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-72678)
- [https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-80/389507](https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-80/389507)

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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-2026-72678 · Markdown: https://rewindex.com/cve/CVE-2026-72678.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-72678 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:13:44.163Z