CVE-2026-63144: 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

mediumCVSS 6.5CVE-2026-63144

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.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 6.5
Published: 2026-07-21
Last updated: 2026-07-22
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-63144

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-631440.24% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 15% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-63144	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[NEW] [medium] Elasticsearch: Multiple vulnerabilities allow DoS and information disclosurecert-bund
unknownMultiple vulnerabilities in Elastic products (July 22, 2026)cert-fr-avis

Recent advisories for Uncontrolled Recursion

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

unknownCVE-2026-67313: axios versions 0.28.0 and later contain uncontrolled recursion in formDataToJSON when processi…nvd · 2026-08-01
unknownCVE-2026-67312: axios versions from 0.28.0 before 0.33.0 and from 1.0.0 before 1.18.0 contain uncontrolled rec…nvd · 2026-08-01
unknownCVE-2026-18140 - Uncontrolled recursion in the aws-smithy-json unknown-key skip path allows unauthenticated re…aws · 2026-07-31
highCVE-2026-18140: Uncontrolled recursion in the unknown-key skip path of the aws-smithy-json runtime crate befor…nvd · 2026-07-30
highCVE-2026-67215: cJSON through 1.7.19 is vulnerable to uncontrolled recursion leading to stack exhaustion when …nvd · 2026-07-29
unknownCVE-2026-66920: Pivotick contains an uncontrolled-recursion vulnerability when processing caller-supplied grap…nvd · 2026-07-28