CVE-2026-72636

Uncontrolled Recursion (CWE-674) in the Elasticsearch wildcard matching helper can lead to a denial of service via Excessive Allocation (CAPEC-130). The matcher used to resolve wildcard patterns against names is implemented recursively and had no bound on recursion depth or on the total number of match operations performed. A search request containing a wildcard pattern with a large number of wildcard groups, evaluated against a sufficiently long name, exhausts the thread stack. Elasticsearch treats a stack overflow as an unrecoverable condition and shuts the node down, so the request terminates the affected node rather than failing gracefully.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-security-update-esa-2026-133/389499	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:elastic:elasticsearch::::::::
	cpe:2.3:a:elastic:elasticsearch::::::::

History

No history.

Information

Published : 2026-08-13 20:17

Updated : 2026-09-01 14:28

NVD link : CVE-2026-72636

Mitre link : CVE-2026-72636

CVE.ORG link : CVE-2026-72636

JSON object : View

Products Affected

elastic

elasticsearch

CWE

CWE-674

Uncontrolled Recursion

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