What is CVE-2026-0543?

CVE-2026-0543 is a medium-severity vulnerability in Elastic Kibana, classified under Improper Input Validation. CVSS score: 6.5/10. Published 2026-01-13.

How severe is CVE-2026-0543?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Resource exhaustion in Elastic Kibana

CVE-2026-0543

Improper Input Validation (CWE-20) in Kibana's Email Connector can allow an attacker to cause an Excessive Allocation (CAPEC-130) through a specially crafted email address parameter. This requires an attacker to have authenticated access with view-level privileges sufficient to execute connector actions. The application attempts to process specially crafted email format, resulting in complete service unavailability for all users until manual restart is performed.

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

EPSS: 0.004 (29.7th percentile) — read the EPSS interpretation.

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.

Affected products

Elastic Kibana — versions 8.0.0, 7.0.0, 9.0.0

Weakness classification (CWE)

References

security@elastic.co (Vendor Advisory)

Frequently asked questions

What is CVE-2026-0543?: CVE-2026-0543 is a medium-severity vulnerability in Elastic Kibana, classified under Improper Input Validation. CVSS score: 6.5/10. Published 2026-01-13.
How severe is CVE-2026-0543?: Medium severity. CVSS v3 base score is 6.5 out of 10.