CVE-2026-0543 | Improper Input Validation in Kibana Email Connector Leading to Excessive Allocation

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.

Published: 2026-01-13 Last update: 2026-01-22 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-0543 is rated Low Risk (32.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-0543

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-14 — 0.06% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-0543

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2026-0543

OS Trackers for CVE-2026-0543

vendor priority summary link
redhat medium — https://access.redhat.com/security/cve/CVE-2026-0543

Affected software / configurations for CVE-2026-0543

Vendor Product Version Raw CPE
elastic kibana >= 7.0.0, <= 7.17.29 cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*
elastic kibana >= 8.0.0, < 8.19.0 cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*
elastic kibana >= 9.0.0, < 9.1.10 cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*
elastic kibana >= 9.2.0, < 9.2.4 cpe:2.3:a:elastic:kibana:*:*:*:*:*:*:*:*

References for CVE-2026-0543

cvelogic Threat Intelligence