6.5
MEDIUM CVSS 3.1
CVE-2026-72656
Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service
Description

Memory Allocation with Excessive Size Value (CWE-789) in the ES|QL query processing of Elasticsearch can lead to denial of service via Excessive Allocation (CAPEC-130). An authenticated user able to submit ES|QL queries could send a specially crafted query whose evaluation allocates an unbounded amount of heap memory, exhausting the available heap on the receiving node and causing the node to become unavailable.

INFO

Published Date :

Aug. 13, 2026, 8:17 p.m.

Last Modified :

Aug. 13, 2026, 9:18 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-72656 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Elastic elasticsearch
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 271b6943-45a9-4f3a-ab4e-976f3fa05b5a
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Apply patches to Elasticsearch to mitigate denial of service via excessive memory allocation in ES|QL query processing.
  • Apply vendor-supplied patches for Elasticsearch.
  • Restrict ES|QL query submission to trusted users.
  • Monitor heap memory usage for ES|QL queries.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-72656.

URL Resource
https://discuss.elastic.co/t/elasticsearch-8-18-0-9-0-0-security-update-esa-2026-111/389495
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-72656 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-72656 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-72656 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-72656 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 13, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-72656', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-13T19:57:27.080993Z'}
  • New CVE Received by [email protected]

    Aug. 13, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Elastic', 'product': 'Elasticsearch', 'versions': [{'status': 'affected', 'version': '8.11.0', 'versionType': 'semver', 'lessThanOrEqual': '8.17.9'}], 'defaultStatus': 'unaffected'}]
    Added Description Memory Allocation with Excessive Size Value (CWE-789) in the ES|QL query processing of Elasticsearch can lead to denial of service via Excessive Allocation (CAPEC-130). An authenticated user able to submit ES|QL queries could send a specially crafted query whose evaluation allocates an unbounded amount of heap memory, exhausting the available heap on the receiving node and causing the node to become unavailable.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-789
    Added Reference https://discuss.elastic.co/t/elasticsearch-8-18-0-9-0-0-security-update-esa-2026-111/389495
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.