CVE-2018-18405 in jQuery
Summary
by MITRE
jQuery v2.2.2 allows XSS via a crafted onerror attribute of an IMG element.
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Analysis
by VulDB Data Team • 05/06/2025
The vulnerability CVE-2018-18405 represents a cross-site scripting flaw in jQuery version 2.2.2 that specifically targets the handling of image error attributes. This issue arises when the library processes HTML content containing malicious onerror attributes within img elements, creating a pathway for attackers to execute arbitrary JavaScript code in the context of the victim's browser. The vulnerability stems from inadequate input sanitization and improper handling of event attributes during HTML parsing operations.
The technical flaw manifests in jQuery's internal DOM manipulation routines where the library fails to properly escape or validate the onerror attribute values when constructing image elements. When a malicious user crafts an image tag with a specially crafted onerror attribute containing javascript code, the vulnerable version of jQuery processes this input without sufficient sanitization, allowing the malicious script to execute when the image fails to load. This particular vulnerability aligns with CWE-79, which describes Cross-Site Scripting flaws in web applications, and demonstrates how client-side libraries can become attack vectors when they fail to properly handle untrusted input.
The operational impact of this vulnerability extends beyond simple script execution, as it enables attackers to perform session hijacking, data exfiltration, and other malicious activities that compromise user browsers. An attacker could craft phishing pages or inject malicious payloads into web applications that use jQuery 2.2.2, potentially leading to full compromise of user sessions and sensitive data exposure. The vulnerability is particularly concerning because jQuery is widely used across thousands of websites, making the potential attack surface extensive and the impact significant.
Organizations should immediately upgrade to jQuery version 3.3.1 or later, which contains the necessary patches to address this vulnerability. The mitigation strategy involves not only updating the library but also implementing proper input validation and sanitization at multiple layers of the application stack. Security practitioners should consider implementing content security policies and monitoring for suspicious script execution patterns. This vulnerability exemplifies the importance of keeping third-party libraries current and demonstrates how seemingly minor flaws in core components can create substantial security risks. The ATT&CK framework categorizes this as a code injection technique, specifically targeting the client-side execution environment through DOM manipulation vulnerabilities.