# CVE-2026-72686: Uncontrolled Recursion in Elasticsearch Leading to Denial of Service

> CVE-2026-72686: Uncontrolled Recursion in Elasticsearch Leading to Denial of Service. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-72686
Last updated: 2026-09-01T15:03:00Z

- Published: 2026-08-13 19:10 UTC · Updated: 2026-09-01 15:03 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: 0.57%, 47th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-674

## Description

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single request containing a crafted user-supplied input. A specific internal component validates the input using a recursive routine and applies no bound to the length of the value being validated, so the validation causes the thread to exhaust its stack. The resulting fatal error is not handled by the surrounding execution paths and terminates the affected node process, producing a denial of service.

## 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-2026-72686)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-72686)
- [https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-78/389505](https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-78/389505)

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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-2026-72686 · Markdown: https://rewindex.com/cve/CVE-2026-72686.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-72686 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:15:23.526Z