SB2021042553 - Multiple vulnerabilities in WordPress

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) XML External Entity injection (CVE-ID: CVE-2021-29447)

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.

2) Security restrictions bypass (CVE-ID: CVE-2021-29450)

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

The vulnerability exists due to application does not properly impose security restrictions within REST API implementation. A remote user with contributor privileges can access password-protected posts and pages.

Remediation

Install update from vendor's website.

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
• https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-pmmh-2f36-wvhq