# CVE-2026-52203: MCMS SSRF in editor via source parameter

Source: https://junglewise.ai/threats/cve-2026-52203-mcms-ssrf-in-editor-via-source-parameter  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-17. Updated: 2026-07-17  
License: CC BY 4.0 with a link back

CVE-2026-52203 · Severity: info · CVSS 5 · Published 2026-07-17

MCMS is a content management system used to build and manage websites. A security flaw in version 6.1.1 allows an attacker with very low-level access to trick the server into making unauthorized requests to internal or external systems. This could lead to the exposure of sensitive internal files or information that should not be publicly accessible.

Technologies: [Mingsoft Mcms](https://junglewise.ai/threats/technologies/mcms). Vendors: [Mingsoft](https://junglewise.ai/threats/vendors/mingsoft).

## Quick answers

**Is CVE-2026-52203 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52203 being exploited in the wild.

**How severe is CVE-2026-52203?** Informational severity, with a CVSS score of 5, published 17 July 2026.

**Which products and versions are affected?** Mingsoft Mcms 6.1.1.

**Is there a fix for CVE-2026-52203?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-52203 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-52203?** Check whether you run Mingsoft Mcms at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in MCMS v.6.1.1 within the editor functionality. The vulnerability is located in the 'source' parameter of the '/ms/editor.do' endpoint when the 'action' parameter is set to 'catchimage'. A remote attacker with low-level privileges can exploit this by sending a crafted POST request containing a malicious URL in the 'source[]' parameter. This allows the attacker to force the server to perform GET requests to arbitrary internal or external locations, potentially leading to the disclosure of sensitive local files or internal network data.

## Affected products

- MCMS MCMS 6.1.1

## Timeline

- 2026-07-16: disclosed: Initial discovery and gist publication
- 2026-07-17: advisory: CVE published to NVD dataset

## References

- [https://gist.github.com/this1slwl/1bfb6996ca7edf6f5d15b5ebc181f337](https://gist.github.com/this1slwl/1bfb6996ca7edf6f5d15b5ebc181f337)

## Related threats

- [MingSoft MCMS SQL injection in custom model import](https://junglewise.ai/threats/cve-2026-88416-mcms-6-1-1-through-6-2-1-has-a-sql-injection-vulnerability-in-the)
- [MCMS stored Cross-Site Scripting in article content field](https://junglewise.ai/threats/cve-2026-88415-mcms-6-1-1-through-6-2-1-is-vulnerable-to-stored-cross-site)
- [MCMS SQL injection in PageAction.verify endpoint](https://junglewise.ai/threats/cve-2026-88414-mcms-6-1-1-through-6-2-1-contains-a-sql-injection-vulnerability)
- [mingSoft MCMS reflected XSS in search.do](https://junglewise.ai/threats/cve-2025-60837-mingsoft-mcms-reflected-xss-in-search-do)
- [mingSoft MCMS arbitrary file upload in upload.do](https://junglewise.ai/threats/cve-2025-60838-mingsoft-mcms-arbitrary-file-upload-in-upload-do)