Threats Tagged 'cve-2026-72636'

CVE-2026-72636 is a medium severity vulnerability in Elasticsearch affecting versions 8.0.0 up to but not including 8.19.20 and 9.0.0 up to but not including 9.4.5. It involves uncontrolled recursion in the wildcard matching helper, which can cause a denial of service by exhausting the thread stack and shutting down the node. This occurs when a search request contains a wildcard pattern with many wildcard groups evaluated against a long name, leading to a stack overflow that Elasticsearch treats as unrecoverable.

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.