# CVE-2026-23919: Insufficient isolation of JavaScript (Duktape) execution context on Zabbix Server

> Insufficient isolation in Zabbix JavaScript contexts allows administrators to leak data from hosts they lack access to.

- **Severity:** High 7.1 (`CVSS:4.0/AV:A/AC:L/AT:P/PR:H/UI:N/VC:H/VI:L/VA:L/SC:H/SI:L/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Mar 2026
- **Updated:** 22 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-23919, GHSA-h55g-ww3m-9hq9, UBUNTU-CVE-2026-23919

## What is CVE-2026-23919?

CVE-2026-23919 is a high-severity vulnerability in Zabbix Zabbix, published on 24 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

For performance reasons Zabbix Server/Proxy reuses JavaScript (Duktape) contexts (used in script items, JavaScript reprocessing, Webhooks). This can lead to confidentiality loss where a regular (non-super) Zabbix administrator leaks data for hosts they do not have access to. A fix has been released that makes the built in Zabbix JavaScript objects read-only, but please be advised that usage of global JavaScript variables is not recommended because their content could be leaked. More information <a href='https://www.zabbix.com/documentation/7.4/en/manual/installation/known_issues#preprocessing-global-variables-are-unsafe'>in Zabbix documentation</a>.

Weakness: CWE-488 (Exposure of Data Element to Wrong Session)

## Which versions are affected by CVE-2026-23919?

It affects 1 product.


Products: Zabbix Zabbix.

## How do I fix CVE-2026-23919?

Apply the vendor's patch.

## Is CVE-2026-23919 being exploited?

There is no known exploitation of CVE-2026-23919 in the wild and no public exploit code.

## Other vulnerabilities in Zabbix Zabbix

- [CVE-2022-23131](https://insights.sbomify.com/CVE-2022-23131/): Zabbix Frontend Authentication Bypass (critical 9.1, exploited in the wild)
- [CVE-2007-0640](https://insights.sbomify.com/CVE-2007-0640/): Memory corruption in n/a (critical 10.0)
- [CVE-2024-42327](https://insights.sbomify.com/CVE-2024-42327/): SQL injection in user.get API (critical 9.9)
- [CVE-2024-22116](https://insights.sbomify.com/CVE-2024-22116/): Remote code execution within ping script (critical 9.9)
- [CVE-2013-3738](https://insights.sbomify.com/CVE-2013-3738/): Code injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-23919 and fix it if it is affected.

What it is: CVE-2026-23919 is a high-severity vulnerability in Zabbix Zabbix, published on 24 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-23919 in the wild and no public exploit code.

Affected product: Zabbix 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-2026-23919/ (Markdown: https://insights.sbomify.com/CVE-2026-23919/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23919
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23919
- OSV: https://osv.dev/vulnerability/CVE-2026-23919

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23919/
Summaries are generated and may contain mistakes; the official description above is the record.