# CVE-2026-59783: Server DoS via binary items

> Attackers can crash Zabbix Server or Proxy by sending NULL bytes in binary items, causing denial of service in MySQL/MariaDB deployments.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **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:** 5 Oct 2026
- **Updated:** 5 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-59783, GHSA-2835-94vr-22j6, UBUNTU-CVE-2026-59783

## What is CVE-2026-59783?

CVE-2026-59783 is a low-severity denial of service vulnerability in Zabbix, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The Zabbix Server/Proxy has a vulnerability where binary items can crash the Server/Proxy on certain NULL byte input leading to potential loss of availability. This only affects deployments where MySQL/MariaDB database is used as the Zabbix database.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-59783?


## How do I fix CVE-2026-59783?

Apply the vendor's patch.

## Is CVE-2026-59783 being exploited?

There is no known exploitation of CVE-2026-59783 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-59783 and fix it if it is affected.

What it is: CVE-2026-59783 is a low-severity denial of service vulnerability in Zabbix, published on 5 Oct 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-2026-59783 in the wild and no public exploit code.

Affected product: Zabbix. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-59783/ (Markdown: https://insights.sbomify.com/CVE-2026-59783/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59783
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59783
- OSV: https://osv.dev/vulnerability/CVE-2026-59783

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59783/
Summaries are generated and may contain mistakes; the official description above is the record.