PatchSiren cyber security CVE debrief
CVE-2026-63136 Elastic CVE debrief
CVE-2026-63136 is a vulnerability in Elasticsearch that can lead to denial of service via Excessive Allocation. A user with search privileges can submit a specially crafted search request that causes a data node to exhaust available heap memory, resulting in node unavailability and cluster degradation. This issue affects Elasticsearch users with search privileges, administrators of Elasticsearch clusters, and security teams monitoring for potential denial of service attacks. The vulnerability is categorized as CWE-400, Uncontrolled Resource Consumption.
- Vendor
- Elastic
- Product
- Elasticsearch
- CVSS
- MEDIUM 6.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-21
- Original CVE updated
- 2026-07-22
- Advisory published
- 2026-07-21
- Advisory updated
- 2026-07-22
Who should care
Users of Elasticsearch with search privileges, administrators of Elasticsearch clusters, and security teams monitoring for potential denial of service attacks should be aware of this vulnerability. They should review and limit search privileges for users, monitor Elasticsearch cluster performance and heap memory usage, and implement compensating controls to detect and prevent excessive search requests.
Technical summary
The vulnerability is caused by uncontrolled resource consumption in Elasticsearch, which can be exploited by a user with search privileges submitting a specially crafted search request. This can lead to excessive allocation of heap memory, causing node unavailability and cluster degradation. The issue requires review of search privileges, monitoring of Elasticsearch cluster performance and heap memory usage, and implementation of compensating controls to detect and prevent excessive search requests.
Defensive priority
Medium
Recommended defensive actions
- Review and limit search privileges for users
- Monitor Elasticsearch cluster performance and heap memory usage
- Implement compensating controls to detect and prevent excessive search requests
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
- Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
- Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
- Check relevant monitoring, detection, and logs for exposed assets that need extra review
Evidence notes
The CVE record was published on 2026-07-21T21:16:52.850Z and was last modified on 2026-07-22T20:37:38.603Z. The NVD entry is currently Awaiting Analysis. Elasticsearch users should verify their deployments and review official advisories for affected scope and severity. Defenders should focus on search privilege limitations and heap memory monitoring.
Official resources
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CVE-2026-63136 CVE record
CVE.org
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CVE-2026-63136 NVD detail
NVD
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Source item URL
nvd_modified
- Source reference
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-21T21:16:52.850Z and has not been modified since then. The NVD entry is currently Awaiting Analysis.