Vulnerability identifier: #VU52549

Vulnerability risk: Medium

CVSSv3.1: 4.9 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-29447

CWE-ID: CWE-611

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
WordPress
Web applications / CMS

Vendor: WordPress.ORG

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

WordPress: 5.7, 5.6 - 5.6.2, 5.5 - 5.5.3, 5.4 - 5.4.4, 5.3 - 5.3.6, 5.2 - 5.2.9, 5.1 - 5.1.8, 5.0 - 5.0.11, 4.9 - 4.9.16, 4.8 - 4.8.15, 4.7 - 4.7.19

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

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.