# CVE-2026-11423: Path Traversal in Altium Enterprise Server Collaboration Service Allows Privilege Escalation

> Authenticated users can exploit path traversal to read server configuration files, exposing credentials and enabling privilege escalation to administrator.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 5 Jun 2026
- **Updated:** 8 Jun 2026
- **Also known as:** GHSA-8mjc-gx82-2m9v

## What is CVE-2026-11423?

CVE-2026-11423 is a critical path traversal vulnerability in Altium Enterprise Server, published on 5 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A path traversal vulnerability exists in the Altium Enterprise Server Collaboration Service due to improper handling of user-supplied filenames in the MCAD and Simulation file download flows. A regular authenticated user can submit a collaboration message containing a crafted filename, which is later used to construct the download path on the server without validation, allowing arbitrary files to be read from the server filesystem.

Because the readable files include the server's master configuration, which stores credentials for privileged accounts, exploitation can lead to authenticating as a system administrator and gaining full control of the server. Altium 365 cloud deployments are not affected.

Weakness: CWE-269 (Improper Privilege Management), CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-11423?


## How do I fix CVE-2026-11423?

No fix has been published for CVE-2026-11423 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-11423 being exploited?

There is no known exploitation of CVE-2026-11423 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-11423 and fix it if it is affected.

What it is: CVE-2026-11423 is a critical path traversal vulnerability in Altium Enterprise Server, published on 5 Jun 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-2026-11423 in the wild and no public exploit code.

Affected product: Altium Enterprise Server. 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-2026-11423/ (Markdown: https://insights.sbomify.com/CVE-2026-11423/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-11423
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-11423
- OSV: https://osv.dev/vulnerability/CVE-2026-11423

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-11423/
Summaries are generated and may contain mistakes; the official description above is the record.