What is CVE-2026-72656?

CVE-2026-72656 is a medium-severity vulnerability in Elastic Elasticsearch, classified under CWE-789. CVSS score: 6.5/10. Published 2026-08-13.

How severe is CVE-2026-72656?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Elastic Elasticsearch

CVE-2026-72656

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.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Elastic Elasticsearch — versions 8.11.0

Weakness classification (CWE)

CWE-789

References

security@elastic.co

Frequently asked questions

What is CVE-2026-72656?: CVE-2026-72656 is a medium-severity vulnerability in Elastic Elasticsearch, classified under CWE-789. CVSS score: 6.5/10. Published 2026-08-13.
How severe is CVE-2026-72656?: Medium severity. CVSS v3 base score is 6.5 out of 10.