XML External Entity injection in WordPress - CVE-2021-29447

Vulnerability details

The vulnerability allows a remote user to gain access to sensitive information.

The vulnerability exists due to insufficient validation of user-supplied XML input in the Media Library. A remote authenticated user with ability to upload files can pass a specially crafted XML code to the affected application and view contents of arbitrary files on the system or initiate requests to external systems.

Successful exploitation of the vulnerability may allow an attacker to view contents of arbitrary file on the server or perform network scanning of internal and external infrastructure.

Affected software

How to mitigate CVE-2021-29447

Links to Public Exploits and PoC-codes

• Exploit #11690 - CVE-2021-29447 (PoC for CVE-2021-29447) (June 20, 2025)
• Exploit #9020 - blind-xxe-controller-CVE-2021-29447 (Arbitrary file read controller based on CVE-2021-29447) (April 30, 2023)
• Exploit #8598 - wordpress-cve-2021-29447 (Exploit WordPress Media Library XML External Entity Injection (XXE) to exfiltrate files.) (November 13, 2022)
• Exploit #7057 - WordPress 5.7 - 'Media Library' XML External Entity Injection (XXE) (Authenticated) (November 25, 2021)
• Exploit #6661 - CVE-2021-29447 () (August 29, 2021)
• Exploit #5513 - CVE-2021-29447 (Wordpress XXE injection 구축 자동화 및 PoC ) (June 1, 2021)
• Exploit #5466 - wordpress_cve-2021-29447 (WordPress XXE vulnerability) (May 24, 2021)

External References

• https://wordpress.org/news/category/security/
• https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-rv47-pc52-qrhh
• https://github.com/0xRar/CVE-2021-29447-PoC

Related Security Bulletins

• Multiple vulnerabilities in WordPress
• Debian update for wordpress