# CVE-2021-47943: Textpattern TextPattern CMS remote code execution via file upload

Source: https://junglewise.ai/threats/cve-2021-47943-textpattern-textpattern-cms-remote-code-execution-via-file-upload  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-10. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2021-47943 · Severity: high · CVSS 8.8 · Published 2026-05-10

TextPattern CMS, a popular open-source content management system, is vulnerable to a security flaw in its file upload system. An attacker with basic user permissions can upload a malicious file to the server and use it to take full control of the website. This could lead to the theft of sensitive data, website defacement, or the complete shutdown of the service.

Technologies: [Textpattern CMS](https://junglewise.ai/threats/technologies/textpattern-cms). Vendors: [Textpattern](https://junglewise.ai/threats/vendors/textpattern).

## Quick answers

**Is CVE-2021-47943 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-47943 being exploited in the wild.

**How severe is CVE-2021-47943?** High severity, with a CVSS score of 8.8, published 10 May 2026.

**Which products and versions are affected?** Textpattern CMS 4.8.7.

**Is there a fix for CVE-2021-47943?** 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-2021-47943 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2021-47943?** Check whether you run Textpattern CMS 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

An authenticated remote code execution (RCE) vulnerability exists in TextPattern CMS 4.8.7 due to unrestricted file uploads (CWE-434). An attacker with low-level authentication can navigate to the 'Files' section of the content area and upload a PHP shell. Because the application does not properly validate or restrict the file types being uploaded to the /textpattern/files/ directory, the attacker can then execute arbitrary system commands by accessing the uploaded file via a web browser and passing commands through GET parameters (e.g., using the PHP system() function). Proof-of-concept exploits are publicly available.

## Affected products

- Textpattern TextPattern CMS 4.8.7

## Timeline

- 2021-06-14: other: Initial exploit published on Exploit-DB
- 2026-05-10: advisory: Vulnerability published by VulnCheck and NVD

## References

- [https://www.exploit-db.com/exploits/49996](https://www.exploit-db.com/exploits/49996)
- [https://www.exploit-db.com/exploits/50415](https://www.exploit-db.com/exploits/50415)
- [https://www.vulncheck.com/advisories/textpattern-cms-remote-code-execution-via-file-upload](https://www.vulncheck.com/advisories/textpattern-cms-remote-code-execution-via-file-upload)

## Related threats

- [Textpattern CMS remote code execution in plugin upload](https://junglewise.ai/threats/cve-2021-47976-textpattern-cms-remote-code-execution-in-plugin-upload)
- [Textpattern CMS broken access control in article management](https://junglewise.ai/threats/cve-2026-30452-textpattern-cms-broken-access-control-in-article-management)
- [Textpattern CMS path traversal in XML-RPC mt_uploadImage](https://junglewise.ai/threats/cve-2026-5344-textpattern-cms-path-traversal-in-xml-rpc-mt-uploadimage)