CVE-2026-72687: CWE-789 Memory Allocation with Excessive Size Value in Elastic Elasticsearch
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.
AI Analysis
Technical Summary
This vulnerability involves a flaw in Elasticsearch's handling of a forged opaque identifier submitted by a low-privileged authenticated user. The system decodes and deserializes this identifier before verifying its legitimacy. However, a size value embedded within the identifier is used to allocate memory without any upper bound or accounting against memory usage controls. This unchecked allocation can exhaust system memory, causing the Elasticsearch node process to terminate and resulting in a denial of service condition.
Potential Impact
The impact is a denial of service caused by a fatal out-of-memory condition that terminates the affected Elasticsearch node process. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is currently documented. Until a fix is available, restricting access to trusted users and monitoring for unusual memory usage may help reduce risk.
CVE-2026-72687: CWE-789 Memory Allocation with Excessive Size Value in Elastic Elasticsearch
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.
CVSS v3.1
Score 6.5medium
Affected software
pkg:maven/org.elasticsearch/elasticsearchRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a flaw in Elasticsearch's handling of a forged opaque identifier submitted by a low-privileged authenticated user. The system decodes and deserializes this identifier before verifying its legitimacy. However, a size value embedded within the identifier is used to allocate memory without any upper bound or accounting against memory usage controls. This unchecked allocation can exhaust system memory, causing the Elasticsearch node process to terminate and resulting in a denial of service condition.
Potential Impact
The impact is a denial of service caused by a fatal out-of-memory condition that terminates the affected Elasticsearch node process. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is currently documented. Until a fix is available, restricting access to trusted users and monitoring for unusual memory usage may help reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- elastic
- Date Reserved
- 2026-08-10T11:17:58.731Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7e1a87bf8831d539b18437
Added to database: 08/13/2026, 19:27:03 UTC
Last enriched: 08/13/2026, 19:42:36 UTC
Last updated: 09/06/2026, 22:52:13 UTC
Views: 51
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