# CVE-2026-0393: CODESYS Visualization - Insufficiently Protected Credentials

> Attackers can expose credentials of low-privileged users during concurrent logins in CODESYS Visualization sessions.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:N/VA:N/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:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 May 2026
- **Updated:** 21 May 2026
- **Also known as:** GHSA-ch6f-rrj9-8j2m

## What is CVE-2026-0393?

CVE-2026-0393 is a medium-severity vulnerability in CODESYS Visualization, published on 21 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

The affected product may expose credentials remotely between low privileged visualization users during concurrent login operations due to insufficient isolation of authentication data. The vulnerability affects only login operations within an active visualization session.

Weakness: CWE-522 (Insufficiently Protected Credentials)

## Which versions are affected by CVE-2026-0393?

It affects 1 product.


Products: Codesys Visualization.

## How do I fix CVE-2026-0393?

No fix has been published for CVE-2026-0393 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-0393 being exploited?

There is no known exploitation of CVE-2026-0393 in the wild and no public exploit code.

## Other vulnerabilities in CODESYS Visualization

- [CVE-2022-1989](https://insights.sbomify.com/CVE-2022-1989/): CODESYS Visualization vulnerable to user enumeration (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-0393 and fix it if it is affected.

What it is: CVE-2026-0393 is a medium-severity vulnerability in CODESYS Visualization, published on 21 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-0393 in the wild and no public exploit code.

Affected product: CODESYS Visualization. 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-2026-0393/ (Markdown: https://insights.sbomify.com/CVE-2026-0393/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-0393
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-0393
- OSV: https://osv.dev/vulnerability/CVE-2026-0393

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-0393/
Summaries are generated and may contain mistakes; the official description above is the record.