Flaw in popular WordPress plug-in Jetpack puts over a million websites at risk

The vulnerability can be exploited to inject malicious code into comments

Owners of WordPress-based websites should update the Jetpack plug-in as soon as possible because of a serious flaw that could expose their users to attacks.

Jetpack is a popular plug-in that offers free website optimization, management and security features. It was developed by Automattic, the company behind WordPress.com and the WordPress open-source project, and has over 1 million active installations.

Researchers from Web security firm Sucuri have found a stored cross-site scripting (XSS) vulnerability that affects all Jetpack releases since 2012, starting with version 2.0.

The issue is located in the Shortcode Embeds Jetpack module which allows users to embed external videos, images, documents, tweets and other resources into their content. It can be easily exploited to inject malicious JavaScript code into comments.

Since the JavaScript code is persistent, it will get executed in users' browsers in the context of the affected website every time they view the malicious comment. This can be used to steal their authentication cookies, including the administrator's session; to redirect visitors to exploits, or to inject search engine optimization (SEO) spam.

"The vulnerability can be easily exploited via wp-comments and we recommend everyone to update asap, if you have not done so yet," said Sucuri researcher Marc-Alexandre Montpas in a blog post.

Sites that don't have the Shortcode Embeds module activated are not affected, but this module provides popular functionality so many websites are likely to have it enabled.

The Jetpack developers have worked with the WordPress security team to push updates to all affected versions through the WordPress core auto-update system. Jetpack versions 4.0.3 or newer contain the fix.

In case users don't want to upgrade to the latest version, the Jetpack developers have also released point releases for all twenty-one vulnerable branches of the Jetpack codebase: 2.0.7, 2.1.5, 2.2.8, 2.3.8, 2.4.5, 2.5.3, 2.6.4, 2.7.3, 2.8.3, 2.9.4, 3.0.4, 3.1.3, 3.2.3, 3.3.4, 3.4.4, 3.5.4, 3.6.2, 3.7.3, 3.8.3, 3.9.7, and 4.0.3.

Join the PC World newsletter!

Error: Please check your email address.

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service
Show Comments

Essentials

Microsoft L5V-00027 Sculpt Ergonomic Keyboard Desktop

Learn more >

Lexar® JumpDrive® S57 USB 3.0 flash drive

Learn more >

Mobile

Lexar® JumpDrive® S45 USB 3.0 flash drive 

Learn more >

Exec

Lexar® JumpDrive® C20c USB Type-C flash drive 

Learn more >

HD Pan/Tilt Wi-Fi Camera with Night Vision NC450

Learn more >

Lexar® Professional 1800x microSDHC™/microSDXC™ UHS-II cards 

Learn more >

Audio-Technica ATH-ANC70 Noise Cancelling Headphones

Learn more >

Budget

Back To Business Guide

Click for more ›

Most Popular Reviews

Latest News Articles

Resources

GGG Evaluation Team

Michael Hargreaves

Windows 10 for Business / Dell XPS

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Kathy Cassidy

STYLISTIC Q702

First impression on unpacking the Q702 test unit was the solid feel and clean, minimalist styling.

Anthony Grifoni

STYLISTIC Q572

For work use, Microsoft Word and Excel programs pre-installed on the device are adequate for preparing short documents.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?