CVE-2026-72656 Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service
An authenticated user can cause a denial of service in Elasticsearch by submitting crafted ES|QL queries that exhaust heap memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72656?
CVE-2026-72656 is a medium-severity denial of service vulnerability in Elastic Elasticsearch, published on 13 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-789
Which versions are affected by CVE-2026-72656?
1 open source package ship an affected version, including elasticsearch. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
elasticsearch Bitnami | From 8.11.0 | 8.17.10 |
Products include Elastic Elasticsearch.
How do I fix CVE-2026-72656?
Upgrade elasticsearch to 8.17.10 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-72656 being exploited?
There is no known exploitation of CVE-2026-72656 in the wild and no public exploit code.
Other vulnerabilities in Elastic Elasticsearch
- CVE-2015-1427 Elasticsearch Groovy Scripting Engine Remote Code Execution
- CVE-2014-3120 Elasticsearch Remote Code Execution
- CVE-2015-5377 Code injection in n/a
- CVE-2026-72649 Deserialization of Untrusted Data in Elasticsearch Leading to Remote Code Execution
- CVE-2026-72642 Use of Out-of-range Pointer Offset in the Elasticsearch Machine Learning Native Inference Process
Sources
Also known as BIT-elasticsearch-2026-72656, GHSA-gpg2-7m3g-5qc5, MINI-4wgg-w5xx-j73v, MINI-6mvh-xhh9-j46m, MINI-7wrh-gcrg-q699.