CVE-2021-41183 Overview
CVE-2021-41183 is a Cross-Site Scripting (XSS) vulnerability in jQuery UI, the official jQuery user interface library. Prior to version 1.13.0, the Datepicker widget improperly handles the values of various *Text options (such as closeText, currentText, prevText, nextText, etc.). When these options accept values from untrusted sources, the content is rendered as HTML rather than plain text, allowing attackers to inject and execute arbitrary JavaScript code in the context of a user's browser session.
Critical Impact
Accepting Datepicker *Text option values from untrusted sources may lead to arbitrary code execution in the user's browser, enabling session hijacking, credential theft, or malicious actions performed on behalf of authenticated users.
Affected Products
- jQuery UI versions prior to 1.13.0
- Drupal (multiple versions)
- Oracle WebLogic Server 12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0
- Oracle PeopleSoft Enterprise PeopleTools 8.58, 8.59
- Oracle Application Express (multiple versions)
- Oracle MySQL Enterprise Monitor
- Oracle Primavera Gateway 18.8.0, 19.12.0, 20.12.0, 21.12.0
- Tenable.sc (multiple versions)
- Fedora 33, 34, 35, 36
- Debian Linux 9.0
- NetApp H-Series firmware (H300S, H500S, H700S, H300E, H500E, H700E, H410S, H410C)
Discovery Timeline
- 2021-10-26 - CVE-2021-41183 published to NVD
- 2024-11-21 - Last updated in NVD database
Technical Details for CVE-2021-41183
Vulnerability Analysis
This XSS vulnerability exists in the jQuery UI Datepicker widget's handling of text configuration options. The widget provides several customizable text options that allow developers to localize or customize the user interface strings displayed in the date picker component. These include options like closeText, currentText, prevText, nextText, and similar *Text configuration parameters.
The fundamental issue is that prior to version 1.13.0, jQuery UI treated these option values as HTML content rather than plain text. When the Datepicker widget renders these strings, it inserts them directly into the DOM without proper sanitization or encoding. This behavior allows an attacker who can control or influence these option values to inject malicious HTML, including script tags or event handlers, that will be executed in the victim's browser.
The attack requires user interaction since the victim must visit a page containing a Datepicker widget configured with malicious option values. The vulnerability can be exploited in applications where user-supplied input is used to configure Datepicker options, or where these options are populated from databases or external sources that may contain attacker-controlled data.
Root Cause
The root cause stems from improper output encoding in the Datepicker widget's rendering logic. The widget used methods like .html() or equivalent DOM manipulation techniques that interpret string content as HTML markup rather than treating it as plain text. This design choice was likely intended to allow HTML formatting in localization strings but inadvertently created an XSS vector when the values came from untrusted sources.
Attack Vector
The attack vector is network-based and requires user interaction. An attacker can exploit this vulnerability through several scenarios:
Stored XSS: If an application stores user-provided text in a database and later uses it to configure Datepicker options, an attacker can inject malicious scripts that execute when other users view the page.
Reflected XSS: If URL parameters or form inputs are used to dynamically set Datepicker text options without sanitization, an attacker can craft a malicious link that executes scripts when clicked.
DOM-based XSS: Applications that read configuration from client-side sources (localStorage, cookies, or URL fragments) and pass them to Datepicker options are vulnerable if those sources can be influenced by an attacker.
When a malicious payload is injected into a *Text option, such as <img src=x onerror=alert('XSS')>, the Datepicker renders it as HTML. The browser then executes the embedded JavaScript, giving the attacker the ability to steal session tokens, perform actions as the authenticated user, or redirect users to malicious sites.
Detection Methods for CVE-2021-41183
Indicators of Compromise
- Unusual JavaScript execution patterns originating from jQuery UI Datepicker DOM elements
- Presence of HTML tags or JavaScript event handlers in Datepicker configuration options within application logs
- Browser console errors related to Content Security Policy violations when Datepicker attempts to execute inline scripts
- User reports of unexpected pop-ups, redirects, or behavior when interacting with date picker fields
Detection Strategies
- Implement Web Application Firewall (WAF) rules to detect XSS payloads in request parameters that may be used for Datepicker configuration
- Monitor client-side JavaScript errors for suspicious script execution attempts related to jQuery UI components
- Conduct regular code reviews and static analysis to identify instances where untrusted input flows into Datepicker *Text options
- Deploy browser-based XSS auditors and Content Security Policy headers to detect and block inline script execution
Monitoring Recommendations
- Enable verbose logging for user inputs that may be used in UI configuration to detect injection attempts
- Implement integrity monitoring for JavaScript library files to detect unauthorized modifications to jQuery UI
- Monitor for anomalous network requests originating from user sessions that may indicate successful XSS exploitation
- Track version inventory of jQuery UI deployments across applications to identify unpatched instances
How to Mitigate CVE-2021-41183
Immediate Actions Required
- Upgrade jQuery UI to version 1.13.0 or later across all applications and embedded components
- Audit application code for any usage of Datepicker *Text options that accept user-supplied or external input
- Implement Content Security Policy headers to restrict inline script execution as a defense-in-depth measure
- Review and update any third-party components or frameworks that bundle jQuery UI (such as Drupal, Oracle products)
Patch Information
The vulnerability is fixed in jQuery UI version 1.13.0, released in October 2021. The fix ensures that values passed to various *Text options are always treated as pure text rather than HTML. This change prevents the rendering of HTML tags embedded in these options, effectively neutralizing XSS payloads.
Vendor-specific patches are available from:
- jQuery UI 1.13.0 Release Notes
- jQuery UI Security Advisory GHSA-j7qv-pgf6-hvh4
- Oracle Critical Patch Update April 2022
- Drupal Security Advisory SA-CORE-2022-002
- Tenable Security Advisory TNS-2022-09
Workarounds
- Do not accept values for Datepicker *Text options from untrusted sources including user input, URL parameters, or external APIs
- Sanitize and encode any dynamic values used for Datepicker configuration before passing them to the widget
- Use server-side HTML entity encoding for any text that will be used in Datepicker options
- Implement strict Content Security Policy headers that disable unsafe-inline to mitigate XSS impact
# Example: Check jQuery UI version in your project
grep -r "jquery-ui" package.json bower.json
npm list jquery-ui
# Update jQuery UI to patched version
npm update jquery-ui@^1.13.0
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
