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

> Authenticated attackers can cause complete service unavailability in Kibana by exploiting improper input validation in the Email Connector.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Jan 2026
- **Updated:** 13 Jan 2026
- **Also known as:** BIT-elk-2026-0543, BIT-kibana-2026-0543, GHSA-p2g6-3qpg-4v6h, MINI-2hhm-v6gh-r5rf, MINI-4pq5-mh2f-835c, MINI-7r6g-459q-r99x, MINI-vxrm-526h-j5pg, MINI-wvmx-rcv6-2gq2, MINI-xf4f-48pv-gr58

## What is CVE-2026-0543?

CVE-2026-0543 is a medium-severity denial of service vulnerability in Elastic Kibana, published on 13 Jan 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-0543?

2 open source packages ship an affected version, including kibana and elk. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kibana` | Bitnami | All versions | 8.19.10, 9.1.10, 9.2.4 |
| `elk` | Bitnami | All versions | 8.19.10, 9.1.10, 9.2.4 |

Products: Elastic Kibana.

## How do I fix CVE-2026-0543?

Upgrade kibana to a fixed version for your release line: 8.19.10, 9.1.10 or 9.2.4.

## Is CVE-2026-0543 being exploited?

There is no known exploitation of CVE-2026-0543 in the wild and no public exploit code.

## Other vulnerabilities in Elastic Kibana

- [CVE-2019-7609](https://insights.sbomify.com/CVE-2019-7609/): Kibana Arbitrary Code Execution (critical 9.8, exploited in the wild)
- [CVE-2025-25015](https://insights.sbomify.com/CVE-2025-25015/): Kibana arbitrary code execution via prototype pollution (critical 9.9)
- [CVE-2024-37288](https://insights.sbomify.com/CVE-2024-37288/): Deserialization in Kibana (critical 9.9)
- [CVE-2023-31415](https://insights.sbomify.com/CVE-2023-31415/): Code injection in Kibana (critical 9.9)
- [CVE-2018-17245](https://insights.sbomify.com/CVE-2018-17245/): Information disclosure in Kibana (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-0543 and fix it if it is affected.

What it is: CVE-2026-0543 is a medium-severity denial of service vulnerability in Elastic Kibana, published on 13 Jan 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-0543 in the wild and no public exploit code.

Affected packages and fixed versions:
- kibana (Bitnami): affected all versions; fixed in 8.19.10, 9.1.10, 9.2.4
- elk (Bitnami): affected all versions; fixed in 8.19.10, 9.1.10, 9.2.4

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-0543/ (Markdown: https://insights.sbomify.com/CVE-2026-0543/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-0543
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-0543
- OSV: https://osv.dev/vulnerability/CVE-2026-0543

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-0543/
Summaries are generated and may contain mistakes; the official description above is the record.