# CVE-2026-63144 — Elastic Elasticsearch

> As of 2026-07-22, CVE-2026-63144 is a MEDIUM-severity vulnerability in Elastic Elasticsearch, CVSS v3.1 6.5, EPSS 0.2% (14.4th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-63144 as of 2026-07-22; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-07-22

## What is CVE-2026-63144?

Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via a specially crafted search request submitted by a low-privileged authenticated user. A user with read-level index access can submit a request that triggers unbounded recursive processing within the Elasticsearch query evaluation component, causing a fatal error that terminates the affected node. In single-node deployments, this results in complete service outage; in multi-node clusters, it causes repeated node restarts and sustained availability degradation.

The record classifies CVE-2026-63144 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 76 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):** 0.2% probability of exploitation in the next 30 days, higher than 14.4% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-07-21, last modified 2026-07-22

## Is CVE-2026-63144 being exploited?

It currently carries a trending score of 33 in the Threadlinqs vulnerability feed.

## Affected products and versions

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

## How to fix CVE-2026-63144

No vendor patch reference has been recorded for CVE-2026-63144 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-2026-63144

No threat campaign in the Threadlinqs corpus currently references CVE-2026-63144, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, NVD, GitHub Security Advisories, FIRST EPSS. Last verified by Threadlinqs on 2026-07-22. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [discuss.elastic.co](https://discuss.elastic.co/t/elasticsearch-8-19-19-9-3-8-9-4-4-security-update-esa-2026-68/388571)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-63144
Full detection coverage and IOCs for threats exploiting CVE-2026-63144 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp