Home Plans Products
Tools
Technology Trends Keyword Lists Browser Extensions
Features
Lead Generation Market Analysis Sales Intelligence
Resources
FAQ About Contact Blog
Account
Login Sign up
Home / Blog / jquery 1.5
Security Advisory

jQuery 1.5 Vulnerabilities: 2 CVEs Affecting 95 Websites

📅 June 07, 2026 ·⏱ 5 min read ·🔒 SiteRecipe Security Team
95 websites still running jquery 1.5  → View full list
2
Total
1
High
1
Medium

jQuery 1.5 remains in use across 95 websites worldwide, despite containing two significant security vulnerabilities that could compromise your site's safety. These flaws range from prototype pollution attacks to stored cross-site scripting (XSS), both capable of allowing malicious actors to inject harmful code or manipulate your website's functionality. Understanding these vulnerabilities and taking immediate action is essential to protect your users and maintain your site's integrity.

In this comprehensive guide, we'll walk you through identifying whether your website uses the vulnerable jQuery 1.5 version, explain what these security risks mean in simple terms, and provide step-by-step instructions to upgrade and secure your site. Whether you're a small business owner or a developer managing multiple projects, this article will help you eliminate these threats efficiently.

What is Jquery 1.5?

jQuery 1.5 is a JavaScript library that was released in 2011 to help developers write cleaner, more efficient code for websites. Think of it as a toolkit that simplifies common web development tasks like animating elements, handling user interactions, and manipulating web page content. Many older websites still rely on jQuery because it was widely popular before modern frameworks like React and Vue became standard.

While jQuery 1.5 served websites well for over a decade, it contains outdated security components that modern cyber threats can exploit. The vulnerabilities discovered in this version allow attackers to modify how the library functions or inject malicious scripts into your pages. This is why major web browsers and security experts recommend upgrading to newer, patched versions of jQuery or replacing it with modern alternatives.

Key Vulnerabilities in Jquery 1.5

2 CVEs found. The most critical are explained below.

HIGH CVE-2021-20084 8.8/10 · CVSS v3.1 ⏱ Immediate
Attackers Can Inject Malicious Code Into Your Website

jQuery Sparkle 1.5.2 has a flaw that allows hackers to inject harmful code into the core functions of your website. This happens because the software doesn't properly check what data is being added to it. Once injected, this code can spread and affect how your entire website operates.

Impact: A hacker could steal visitor data, deface your website, redirect users to malicious sites, or take control of your website's functionality. Your visitors and business reputation could be at serious risk.

↗ View on NVD
MEDIUM CVE-2024-5425 6.4/10 · CVSS v3.1 ⏱ Within 7 days
Hackers Can Hide Malicious Code in Lightbox Titles

The WP jQuery Lightbox plugin doesn't properly check title text before displaying it on your site. This allows someone with contributor access (like a staff member) to hide malicious code in image titles. When visitors view these images, the hidden code can execute on their browsers.

Impact: Attackers could steal visitor information, hijack user sessions, spread malware, or perform actions on behalf of your website visitors. This could lead to data breaches and loss of customer trust.

↗ View on NVD

Is your website running Jquery 1.5?

Scan your site in 30 seconds. Used by 500+ web agencies.

How to Check If Your Website Is Affected

How to Fix These Vulnerabilities

Conclusion

The vulnerabilities in jQuery 1.5 represent a serious security risk that shouldn't be ignored. With prototype pollution and XSS attacks becoming increasingly sophisticated, updating your jQuery library is one of the most straightforward ways to protect your website and users from potential breaches. Taking action today prevents tomorrow's security incidents and maintains your site's credibility.

Don't leave your website's security to chance. Use SiteRecipe.com's automated vulnerability detection tool to scan your entire site for outdated libraries, security flaws, and compliance issues in minutes. Our platform identifies risks like jQuery 1.5 vulnerabilities and guides you toward safe, tested solutions—all without requiring technical expertise. Start your free security audit today and get peace of mind knowing your website is protected.

Frequently Asked Questions

What is prototype pollution and how does CVE-2021-20084 affect my website?
Prototype pollution is an attack where hackers modify core JavaScript object properties to alter how your website functions. CVE-2021-20084 allows attackers to inject malicious properties into jQuery's core objects, potentially giving them control over site behavior, stealing user data, or redirecting visitors to harmful pages.
Can an attacker execute attacks without users knowing about it?
Yes, both vulnerabilities (prototype pollution and XSS) can operate silently in the background. Users may not notice anything unusual while attackers harvest data, inject advertisements, or steal credentials. This is why proactive security scanning and updates are crucial.
Will upgrading jQuery break my website's functionality?
Modern jQuery versions (3.x and above) maintain backward compatibility with most older code, though some deprecated features may need adjustment. Testing is essential after any upgrade. SiteRecipe.com can help identify compatibility issues and guide safe upgrades with minimal disruption.
How often should I check for vulnerabilities like these?
Security best practices recommend scanning for vulnerabilities at least monthly, or immediately after updating any library or plugin. Continuous monitoring services like SiteRecipe.com can alert you automatically whenever new vulnerabilities are discovered in your site's technologies.

Generate white-label reports for your clients

Web agencies use SiteRecipe to produce branded PDF security reports in 30 seconds.

DISCLAIMER: This report is based on publicly available CVE data from the National Vulnerability Database (NVD) maintained by NIST. Detection of a technology version does not confirm active exploitation on any specific website. For informational purposes only. SiteRecipe is not responsible for actions taken based on this report. Always consult a qualified security professional.

Source: nvd.nist.gov · Published: June 07, 2026 · SiteRecipe.com