Elasticsearch Recursion DoS via Malicious Query (CVE-2026-63144)
CVE-2026-63144 Published on July 21, 2026
Uncontrolled Recursion in Elasticsearch Leading to Denial of Service
Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via a specially crafted search request submitted by a low-privileged authenticated user. A user with read-level index access can submit a request that triggers unbounded recursive processing within the Elasticsearch query evaluation component, causing a fatal error that terminates the affected node. In single-node deployments, this results in complete service outage; in multi-node clusters, it causes repeated node restarts and sustained availability degradation.
Vulnerability Analysis
CVE-2026-63144 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
What is a Stack Exhaustion Vulnerability?
The product does not properly control the amount of recursion which takes place, consuming excessive resources, such as allocated memory or the program stack.
CVE-2026-63144 has been classified to as a Stack Exhaustion vulnerability or weakness.
Products Associated with CVE-2026-63144
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Affected Versions
Elasticsearch:- Version 9.4.0, <= 9.4.3 is affected.
- Version 9.3.0, <= 9.3.7 is affected.
- Version 8.19.0, <= 8.19.18 is affected.