What is CVE-2026-72647?

CVE-2026-72647 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Recursion. CVSS score: 6.5/10. Published 2026-08-13.

How severe is CVE-2026-72647?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Elastic Elasticsearch

CVE-2026-72647

Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via Serialized Data with Nested Payloads (CAPEC-230). An authenticated user holding only read privileges on a single index can submit one specially crafted search request whose deeply nested structure is processed without a depth limit, exhausting the thread stack and terminating the affected node.

Published 2026-08-13 · last modified 2026-09-01.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.004 (33.8th percentile), scored 2026-09-27.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Elastic Elasticsearch — versions 8.0.0, 9.0.0

Weakness classification (CWE)

CWE-674 — Uncontrolled Recursion

References

discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026… (Vendor Advisory)

Frequently asked questions

What is CVE-2026-72647?: CVE-2026-72647 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Recursion. CVSS score: 6.5/10. Published 2026-08-13.
How severe is CVE-2026-72647?: Medium severity. CVSS v3 base score is 6.5 out of 10.