# CVE-2026-102409 — Elastic Elasticsearch

> As of 2026-10-06, CVE-2026-102409 is a MEDIUM-severity vulnerability in Elastic Elasticsearch, CVSS v3.1 6.5, EPSS 0.3% (21.1th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-102409, most recently “Elastic Patches 14 Security Flaws Including Kibana Cross-Tenant Data Interception (CVE-2026-102406)”.

**Last updated:** 2026-10-06

## What is 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).

The record classifies CVE-2026-102409 under weakness class [CWE-674](https://intel.threadlinqs.com/cwe/CWE-674). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 4 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 6.5 — MEDIUM (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 21.1% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 4.1/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-10-06

## Is CVE-2026-102409 being exploited?

It currently carries a trending score of 39 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Elastic](https://intel.threadlinqs.com/vendors/elastic): Elasticsearch

## How to fix CVE-2026-102409

No vendor patch reference has been recorded for CVE-2026-102409 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-102409

1 tracked threat in the Threadlinqs corpus references CVE-2026-102409, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Elastic Patches 14 Security Flaws Including Kibana Cross-Tenant Data Interception (CVE-2026-102406)](https://intel.threadlinqs.com/threat/TL-2026-3268) — HIGH · 2026-10-10

## Sources

Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [discuss.elastic.co](https://discuss.elastic.co/t/elasticsearch-9-4-8-9-5-5-security-update-esa-2026-190/390863)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-102409
Full detection coverage and IOCs for threats exploiting CVE-2026-102409 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp