What is CVE-2026-102409?

CVE-2026-102409 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Recursion. CVSS score: 6.5/10. Published 2026-10-06.

How severe is CVE-2026-102409?

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

Vulnerability in Elastic Elasticsearch

CVE-2026-102409

Uncontrolled Recursion (CWE-674) in Elasticsearch can allow an authenticated user with low privileges to terminate an Elasticsearch node, resulting in denial of service, via Excessive Allocation (CAPEC-130).

Published 2026-10-06 · last modified 2026-10-07.

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

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Elastic Elasticsearch

Weakness classification (CWE)

CWE-674 — Uncontrolled Recursion

References

discuss.elastic.co/t/elasticsearch-9-4-8-9-5-5-security-update-esa-2026-190/390…

Frequently asked questions

What is CVE-2026-102409?: CVE-2026-102409 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Recursion. CVSS score: 6.5/10. Published 2026-10-06.
How severe is CVE-2026-102409?: Medium severity. CVSS v3 base score is 6.5 out of 10.