# CVE-2026-53906: Path Disclosure and Path Traversal in MCO

> Attackers can write files to arbitrary locations and disclose server paths via improper filename validation in MCO's export and upload features.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Jul 2026
- **Updated:** 1 Jul 2026
- **Also known as:** GHSA-qwcf-5293-mm28

## What is CVE-2026-53906?

CVE-2026-53906 is a medium-severity path traversal vulnerability in MyComplianceOffice MCO, published on 1 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

MCO is vulnerable to Path Disclosure and Path Traversal in file handling functionality related to data export and upload. Improper validation of the filename parameter allows writing files to arbitrary locations as well as indirect disclosure of absolute server paths through error messages.

Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), CWE-209 (Generation of Error Message Containing Sensitive Information)

## Which versions are affected by CVE-2026-53906?

It affects 1 product.


Products: Mycomplianceoffice Mycomplianceoffice.

## How do I fix CVE-2026-53906?

No fix has been published for CVE-2026-53906 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-53906 being exploited?

There is no known exploitation of CVE-2026-53906 in the wild and no public exploit code.

## Other vulnerabilities in MyComplianceOffice MCO

- [CVE-2026-53902](https://insights.sbomify.com/CVE-2026-53902/): Privilege Escalation in MCO (high 7.1)
- [CVE-2026-53908](https://insights.sbomify.com/CVE-2026-53908/): User Enumeration in MCO (medium 6.9)
- [CVE-2026-53903](https://insights.sbomify.com/CVE-2026-53903/): Insecure Direct Object Reference in MCO (medium 5.3)
- [CVE-2026-53905](https://insights.sbomify.com/CVE-2026-53905/): Unauthorized Access to Administrator ACL View in MCO (medium 5.3)
- [CVE-2026-53909](https://insights.sbomify.com/CVE-2026-53909/): Arbitrary File Upload in MCO (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53906 and fix it if it is affected.

What it is: CVE-2026-53906 is a medium-severity path traversal vulnerability in MyComplianceOffice MCO, published on 1 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-53906 in the wild and no public exploit code.

Affected product: MyComplianceOffice MCO. 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-2026-53906/ (Markdown: https://insights.sbomify.com/CVE-2026-53906/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53906
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53906
- OSV: https://osv.dev/vulnerability/CVE-2026-53906

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53906/
Summaries are generated and may contain mistakes; the official description above is the record.