jQuery: The Silent Security Crisis in Open Source (And How to Fix It in Minutes)

jQuery is the most widely used JavaScript library on the web, powering everything from small business websites to enterprise applications. Yet, according to the 2025 Open Source Security and Risk Analysis (OSSRA) Report, it is also one of the biggest security liabilities in modern software. The report found that jQuery was present in 32 percent of scanned codebases, making it the most commonly used vulnerable component. Worse, 8 of the top ten high-risk vulnerabilities in the report were jQuery-related.

Despite its continued popularity, many organizations are running outdated versions riddled with known security flaws. These vulnerabilities aren’t just theoretical—they are actively exploited in the wild. If your application still uses an outdated version of jQuery, it is one of the easiest targets for attackers today.

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Why jQuery is the Biggest Security Threat in Open Source

jQuery's security risks stem from three key factors:

1. Widespread use – As a dependency in millions of projects, any vulnerability in jQuery has massive potential impact.
2. Legacy code that never gets updated – Many businesses continue running versions of jQuery that are years out of date, leaving them vulnerable to exploits that have long been patched.
3. Cross-site scripting (XSS) issues – The most common jQuery vulnerabilities allow attackers to inject malicious scripts into web applications, stealing data or hijacking user sessions.

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The Worst jQuery Vulnerabilities (And Why They Still Matter)

The OSSRA report highlights multiple critical jQuery vulnerabilities still found in the wild. Here are some of the most dangerous:

1. Cross-site scripting (XSS) in jQuery's HTML parser

• CVE-2020-11023 
• CVE-2020-11022

These vulnerabilities allow attackers to execute arbitrary JavaScript by manipulating how jQuery handles <option> elements in HTML. These flaws have been exploited in real-world attacks, allowing hackers to steal sensitive user data.

2. Cross-site scripting (XSS) in jQuery event handlers

• CVE-2019-11358 

This vulnerability allows attackers to inject malicious scripts into web pages by exploiting how jQuery processes user input in event handlers. If your application is running jQuery before 3.4.0, it remains vulnerable to XSS attacks that can steal session data, manipulate page content, or hijack user interactions.

3. Cross-site scripting (XSS) in jQuery AJAX requests

• CVE-2015-9251 

Older versions of jQuery improperly handle cross-domain AJAX requests, allowing attackers to execute malicious JavaScript responses from untrusted sources. This XSS vulnerability can be exploited to steal user data, hijack sessions, or inject rogue content. Even though it was discovered years ago, many applications still use vulnerable versions of jQuery, leaving them exposed.

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Why These Vulnerabilities Won’t Go Away

The biggest problem with jQuery security isn’t the vulnerabilities—it’s the fact that people don’t update. The OSSRA report found that:

• 91% of codebases contain outdated open source components
• 90% of jQuery instances found were more than four years out of date
• Many applications still use jQuery 1.x and 2.x, which haven’t been supported for years

Developers are often hesitant to update because of breaking changes or dependencies in third-party plugins. This means that even as newer versions fix security issues, the majority of jQuery users remain vulnerable.

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How to Fix This Instantly with HeroDevs' jQuery NES

Manually updating jQuery across an application can be time-consuming and risky. Many organizations avoid it because of the potential for breaking changes, dependency issues, or simply not having the bandwidth to test updates.

This is exactly why we built HeroDevs’ jQuery NES.

HeroDevs’ jQuery NES is a drop-in replacement for outdated jQuery versions that provides ongoing security patches without breaking your application. It works in minutes, requires no major refactoring, and ensures that your jQuery-dependent code stays secure, compliant, and functional.

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Not sure if your site is still running an outdated version of jQuery? 

Use Healthy Web to instantly check for security risks. This free tool scans your website and detects old, vulnerable versions of jQuery, helping you understand your exposure. If it finds outdated jQuery, don’t wait—HeroDevs’ jQuery NES provides a drop-in security fix without breaking your application.

Why Use jQuery NES?

• Instant security updates – Fixes vulnerabilities without requiring a full migration.
• No breaking changes – Works with existing applications and plugins.
• Compliance assurance – Keeps your software aligned with security standards.
• No maintenance headaches – We handle updates, so you don’t have to.

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Final Thoughts: Outdated jQuery is a Liability, But It’s Fixable

jQuery played an essential role in web development for years, but today, it is one of the most actively exploited pieces of software in the open source ecosystem. The 2025 OSSRA report makes it clear: if your organization is still using an outdated version of jQuery, you are inviting attackers in.

Security doesn’t come from hoping you won’t be targeted—it comes from actively removing known risks. Instead of wrestling with a manual update, let HeroDevs’ jQuery NES solve the problem for you in minutes.

Stop running vulnerable jQuery. Secure it today with jQuery NES. Contact us today.