CVE-2026-42397 Elastic CVE debrief

Who should care

Users of Elastic Kibana, especially those with authenticated access to Entity Analytics endpoints, should be aware of this vulnerability and take steps to mitigate it. This includes updating Kibana to a version that addresses this vulnerability, restricting access to Entity Analytics endpoints to only necessary users, and monitoring Kibana logs for excessive resource consumption. Additionally, implementing rate limiting and monitoring for suspicious activity can help prevent exploitation. Review and limit input values to Entity Analytics endpoints to prevent oversized input values. Compensating controls, such as restricting access to affected endpoints, can also be effective.

Technical summary

The vulnerability, classified as CWE-770 (Allocation of Resources Without Limits or Throttling), allows an authenticated user to submit a specially crafted request to affected Entity Analytics endpoints with an oversized input value. This causes excessive resource consumption, potentially rendering Kibana unavailable. The CVSS score for this vulnerability is 6.5, with a severity rating of MEDIUM. To address this vulnerability, users should review compensating controls for exposed systems while remediation is scheduled and verified. Checking relevant monitoring, detection, and logs for exposed assets that need extra review is also essential. Tracking exceptions, retesting remediated assets, and closing the item only after evidence is documented are critical steps in the remediation process.

Defensive priority

Medium priority due to the potential for denial of service and the relatively low CVSS score. Users should focus on updating Kibana to a version that addresses this vulnerability and restrict access to Entity Analytics endpoints to only necessary users. Monitoring Kibana logs for excessive resource consumption is also recommended. Implementing rate limiting and monitoring for suspicious activity can help prevent exploitation. Review and limit input values to Entity Analytics endpoints to prevent oversized input values. Compensating controls, such as restricting access to affected endpoints, can also be effective. Tracking exceptions and retesting remediated assets is crucial to ensure the vulnerability is fully addressed. An owner should be assigned for follow-up on affected product deployments in managed environments. The official advisory or CVE record should be reviewed to validate affected scope, severity, and vendor guidance. Relevant monitoring, detection, and logs should be checked for exposed assets that need extra review. Affected operator, platform, vulnerability-management, and security-team impact should be considered when prioritizing remediation efforts. This vulnerability has a CVSS score of 6.5 and a severity rating of MEDIUM, indicating a moderate level of risk. Users of Elastic Kibana, especially those with authenticated access to Entity Analytics endpoints, should be aware of this vulnerability and take steps to mitigate it. The vulnerability allows an authenticated user to submit a specially crafted request to affected Entity Analytics endpoints with an oversized input value, causing excessive resource consumption and potentially rendering Kibana unavailable. To address this vulnerability, users should review compensating controls for exposed systems while remediation is scheduled and verified. Checking relevant monitoring, detection, and logs for exposed assets that need extra review is also essential. Tracking exceptions, retesting remediated assets, and closing the item only after evidence is documented are critical steps in the remediation process. An executive overview of the vulnerability is necessary to understand the affected product,

Recommended defensive actions

• Review and limit input values to Entity Analytics endpoints
• Implement rate limiting and monitoring for suspicious activity
• Ensure Kibana is updated to a version that addresses this vulnerability
• Restrict access to Entity Analytics endpoints to only necessary users
• Monitor Kibana logs for excessive resource consumption

Evidence notes

The CVE record was published on 2026-07-21T20:17:00.593Z and was last modified on 2026-07-22T20:37:38.603Z. The NVD entry is currently Awaiting Analysis. The vulnerability was reported by Elastic and is related to CWE-770. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the vendor. The CVE record and NVD entry provide the most up-to-date information on this vulnerability.

Official resources