CVE-2026-28871 in Safari
Summary
by MITRE • 03/25/2026
A logic issue was addressed with improved checks. This issue is fixed in Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4. Visiting a maliciously crafted website may lead to a cross-site scripting attack.
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Analysis
by VulDB Data Team • 05/02/2026
This vulnerability represents a cross-site scripting weakness that emerged due to insufficient input validation mechanisms within the web browser's rendering engine. The issue stems from a logic flaw in how Safari processes web content, particularly when handling maliciously crafted websites that contain crafted javascript payloads or other malicious code. The vulnerability allows attackers to inject executable code into web pages viewed by users, potentially enabling unauthorized access to user data, session hijacking, or redirection to malicious sites. This type of vulnerability falls under the category of CWE-79 - Improper Neutralization of Input During Web Page Generation, which is a fundamental weakness in web application security where user-supplied data is not properly sanitized before being rendered in web pages.
The technical implementation of this vulnerability involves the browser's failure to adequately validate and sanitize user-provided content during the page rendering process. When a user visits a malicious website, the crafted content can exploit the logic gap in Safari's content processing mechanisms, allowing malicious scripts to execute in the context of the user's session. This creates a persistent threat vector that can be exploited across multiple platforms including iOS and macOS operating systems. The vulnerability's impact is particularly concerning given that it affects the core browser functionality that users interact with daily, making it a high-severity issue that requires immediate attention. According to ATT&CK framework, this vulnerability maps to T1059.001 - Command and Scripting Interpreter: JavaScript, as it enables the execution of malicious javascript code through the browser's rendering engine.
The operational impact of this vulnerability extends beyond simple script execution to potentially compromise user privacy and system integrity. Attackers could leverage this weakness to steal cookies, session tokens, or other sensitive user information that would normally be protected by the browser's security model. The attack surface is broad as any user visiting a compromised website could be affected, making this a significant concern for enterprise environments where users may inadvertently navigate to malicious sites. The vulnerability affects multiple Apple platforms including iOS, iPadOS, and macOS, indicating a systemic issue within the browser's security architecture rather than a platform-specific problem. Organizations should consider implementing additional network-level protections and user education initiatives while awaiting the deployment of the official security patches. The fix requires comprehensive validation of all web content and proper sanitization of user inputs before execution, aligning with security best practices outlined in OWASP's top ten web application security risks.
The remediation process involves updating affected systems to the patched versions of Safari and the corresponding operating systems, with the specific versions mentioned including Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, and macOS Tahoe 26.4. Security administrators should prioritize deployment of these patches across all affected devices and monitor for any potential exploitation attempts. The fix demonstrates Apple's approach to addressing security gaps through improved input validation and enhanced content sanitization mechanisms. Organizations should also consider implementing web application firewalls and content security policies to add additional layers of protection against similar vulnerabilities. Regular vulnerability assessments and penetration testing should be conducted to identify potential similar weaknesses in other web applications and browser extensions that may present similar attack vectors.