BIT-wordpress-multisite-2021-29447: Medium severity WordPress WordPress vulnerability

Q: Who can exploit this issue?

An authenticated user who can upload files through the Media Library, such as an Author, can exploit it. The issue is remotely reachable but requires low-privileged account access.

Q: Which deployments are affected?

The issue requires WordPress to be running on PHP 8. WordPress 5.7.1 includes a fix, and older affected WordPress branches received fixes through minor releases.

Q: What could an attacker access?

A successful attack can allow access to internal files through an XML external entity attack. The provided impact information indicates confidentiality impact, with no stated integrity or availability impact.

Q: What should be done if an immediate upgrade is not possible?

Restrict Media Library upload capability to trusted users and review accounts with roles, such as Author, that can upload files. Keep WordPress automatic updates enabled so applicable minor-release fixes can be applied.

Published Apr 15, 2021

Updated

Wordpress is an open source CMS. A user with the ability to upload files (like an Author) can exploit an XML parsing issue in the Media Library leading to XXE attacks. This requires WordPress installation to be using PHP 8. Access to internal files is possible in a successful XXE attack. This has been patched in WordPress version 5.7.1, along with the older affected versions via a minor release. We strongly recommend you keep auto-updates enabled.

Affected Software

1 affected component

WordPress WordPress<5.7.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade WordPress to a version that resolves this vulnerability.
Fixed in 5.7.1
Configuration
Keep WordPress auto-updates enabled
WordPress auto-updates = enabled

Event History

Apr 15, 2021

CVE Published

via OSV·09:15 PM

Data Sourced

via OSV·09:15 PM

DescriptionSeverity

Frequently Asked Questions

Who can exploit this issue?

An authenticated user who can upload files through the Media Library, such as an Author, can exploit it. The issue is remotely reachable but requires low-privileged account access.

Which deployments are affected?

The issue requires WordPress to be running on PHP 8. WordPress 5.7.1 includes a fix, and older affected WordPress branches received fixes through minor releases.

What could an attacker access?

A successful attack can allow access to internal files through an XML external entity attack. The provided impact information indicates confidentiality impact, with no stated integrity or availability impact.

What should be done if an immediate upgrade is not possible?

Restrict Media Library upload capability to trusted users and review accounts with roles, such as Author, that can upload files. Keep WordPress automatic updates enabled so applicable minor-release fixes can be applied.

BIT-wordpress-multisite-2021-29447: Medium severity WordPress WordPress vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Who can exploit this issue?

Which deployments are affected?

What could an attacker access?

What should be done if an immediate upgrade is not possible?

Company

Resources

Contact

Frequently Asked Questions

Who can exploit this issue?

Which deployments are affected?

What could an attacker access?

What should be done if an immediate upgrade is not possible?