Improper input validation in Elastic Kibana

CVE-2026-56151

Improper Input Validation (CWE-20) in Kibana can lead to a denial of service via Input Data Manipulation (CAPEC-153). An authenticated user can submit a specially crafted Fleet policy input that is not correctly validated, which can render Fleet agent, server, and policy management functionality unavailable.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (38.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-56151: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-56151?
CVE-2026-56151 is a medium-severity vulnerability in Elastic Kibana, classified under Improper Input Validation. CVSS score: 6.5/10. Published 2026-07-01.
How severe is CVE-2026-56151?
Medium severity. CVSS v3 base score is 6.5 out of 10.