CVE-2026-72638 Elastic CVE debrief

Who should care

Elasticsearch administrators, security teams, and IT professionals responsible for Elasticsearch deployments should review and apply vendor remediation to prevent potential denial of service via Input Data Manipulation. Additionally, vulnerability management teams and platform operators should assess the affected scope of Elasticsearch deployments and prioritize remediation efforts based on the severity of potential impact on their environment. Security teams should also monitor for suspicious activity related to custom analysis definitions and inventory affected systems for potential exposure. IT professionals should ensure that proper change management and exception tracking procedures are in place for Elasticsearch updates and verify the effectiveness of compensating controls where applicable. This should be done in conjunction with reviewing official advisories and CVE records to validate affected scope, severity, and vendor guidance, and planning vendor-supported updates or mitigations through normal change control where exposure is confirmed. Compensating controls should be reviewed for exposed systems while remediation is scheduled and verified, and relevant monitoring, detection, and logs should be checked for exposed assets that need extra review. Exceptions, retest remediated assets, and close the item only after evidence is documented. This CVE record was published on 2026-08-13T20:17:24.310Z and has not been modified since then, so immediate action is recommended to prevent potential exploitation of this vulnerability in Elasticsearch deployments. Review compensating controls for exposed systems while remediation is scheduled and verified. Check relevant monitoring, detection, and logs for exposed assets that need extra review. Track exceptions, retest remediated assets, and close the item only after evidence is documented. Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed. Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. This is

Technical summary

An authenticated user holding only low-privileged index creation permissions can submit a single request containing a specially crafted, malformed custom analysis definition that is resolved recursively without a cycle or depth check, exhausting the thread stack and terminating the affected node. This vulnerability affects Elasticsearch deployments, particularly those with low-privileged users able to create indexes. The vulnerability can be exploited via Input Data Manipulation, leading to a denial of service.

Defensive priority

Medium-priority defensive review recommended due to potential denial of service via Input Data Manipulation.

Recommended defensive actions

• Review and apply vendor remediation for Elasticsearch vulnerability
• Implement compensating controls to detect and prevent Input Data Manipulation
• Monitor for suspicious activity related to custom analysis definitions
• Inventory and assess affected scope of Elasticsearch deployments
• Exception tracking and retest procedures for Elasticsearch updates

Evidence notes

Evidence from official CVE Program record and NIST NVD detail page supports the existence of an Uncontrolled Recursion vulnerability in Elasticsearch, which can lead to denial of service. An authenticated user with low-privileged index creation permissions can submit a specially crafted, malformed custom analysis definition that is resolved recursively without a cycle or depth check, exhausting the thread stack and terminating the affected node.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.