# CVE-2026-72636: Uncontrolled Recursion in Elasticsearch Wildcard Matching Leading to Denial of Service

> CVE-2026-72636: Uncontrolled Recursion in Elasticsearch Wildcard Matching Leading to Denial of Service. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-72636
Last updated: 2026-09-01T14:28:15Z

- Published: 2026-08-13 19:14 UTC · Updated: 2026-09-01 14:28 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: 0.42%, 36th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-674

## Description

Uncontrolled Recursion (CWE-674) in the Elasticsearch wildcard matching helper can lead to a denial of service via Excessive Allocation (CAPEC-130). The matcher used to resolve wildcard patterns against names is implemented recursively and had no bound on recursion depth or on the total number of match operations performed. A search request containing a wildcard pattern with a large number of wildcard groups, evaluated against a sufficiently long name, exhausts the thread stack. Elasticsearch treats a stack overflow as an unrecoverable condition and shuts the node down, so the request terminates the affected node rather than failing gracefully.

## 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-2026-72636)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-72636)
- [https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-security-update-esa-2026-133/389499](https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-security-update-esa-2026-133/389499)

---

_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/)_


---
Canonical: https://rewindex.com/cve/CVE-2026-72636 · Markdown: https://rewindex.com/cve/CVE-2026-72636.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-72636 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:12:46.285Z