CVE-2026-72687 Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service
A low-privileged user can cause a fatal out-of-memory crash in Elasticsearch by submitting a request with a forged identifier, leading to denial of service.
- 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-2026-72687?
CVE-2026-72687 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
A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier. Elasticsearch decodes and deserializes the identifier before confirming that it was legitimately issued by the cluster, and a size value carried inside the identifier drives an allocation that is neither capped nor accounted for by the available memory-usage controls. The resulting out-of-memory condition is fatal and terminates the affected node process, resulting in a denial of service.
Weakness: CWE-789
Which versions are affected by CVE-2026-72687?
1 open source package ship an affected version, including elasticsearch. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
elasticsearch Bitnami | From 8.0.0 | 8.19.20, 9.4.5, 9.5.1 |
Products include Elastic Elasticsearch.
How do I fix CVE-2026-72687?
Upgrade elasticsearch to a fixed version for your release line: 8.19.20, 9.4.5 or 9.5.1.
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-2026-72687 being exploited?
There is no known exploitation of CVE-2026-72687 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-2026-72687, CLEANSTART-2026-BL26751, CLEANSTART-2026-ZB19187, GHSA-gf23-7gr9-6992, MINI-28wx-wgv4-qw9v, MINI-33xr-97r2-6j2v and 19 more.