CVE-2015-5904 in iOS
Summary
by MITRE
Safari in Apple iOS before 9 allows remote attackers to spoof the relationship between URLs and web content via a crafted web site.
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Analysis
by VulDB Data Team • 06/16/2022
The vulnerability identified as CVE-2015-5904 represents a significant security flaw in Apple iOS Safari browsers prior to version 9, specifically targeting the browser's handling of URL relationships and web content presentation. This issue stems from insufficient validation mechanisms that allow malicious actors to manipulate how web addresses are displayed and interpreted by the browser. The flaw enables attackers to create deceptive web pages that appear to be legitimate sites while actually serving different content, effectively bypassing user trust mechanisms that rely on URL authenticity. Such a vulnerability directly impacts the fundamental security principle of web browser integrity by undermining the user's ability to accurately verify website identity and content source.
The technical implementation of this vulnerability involves the manipulation of browser rendering behaviors and URL handling mechanisms within Safari's web engine. Attackers can craft malicious websites that exploit how Safari processes and displays URL information, creating scenarios where the displayed address does not accurately reflect the actual content being served or the underlying network connections being established. This typically occurs through sophisticated manipulation of HTML elements, JavaScript behaviors, and potentially CSS properties that influence how the browser's address bar and content relationship are presented to users. The vulnerability leverages weaknesses in the browser's security model where the visual representation of web addresses becomes decoupled from the actual content delivery mechanisms.
The operational impact of CVE-2015-5904 extends beyond simple phishing attacks, creating an environment where sophisticated social engineering campaigns can gain increased effectiveness through technical manipulation. Users who rely on URL verification as a security control may be deceived into trusting malicious sites that appear legitimate due to the spoofed URL relationship. This vulnerability particularly affects users who perform sensitive transactions or access confidential information through Safari, as the deception could lead to credential theft, financial fraud, or data compromise. The attack vector typically involves users visiting compromised websites through various means such as malicious email links, compromised advertisements, or social media sharing, where the deception occurs during the browsing session rather than through initial access mechanisms.
Security professionals should recognize this vulnerability as a variant of broader issues related to web browser security and user interface deception, aligning with CWE-601 URL Redirection to Untrusted Site and ATT&CK technique T1566 for Phishing. The flaw demonstrates the critical importance of maintaining strong browser security boundaries and validating all user interface elements against their underlying content. Organizations should implement comprehensive security awareness training to help users recognize potential deception scenarios and maintain updated browser versions. The recommended mitigation strategy involves immediate deployment of iOS updates to version 9 or later, which includes enhanced URL validation mechanisms and improved handling of web content relationships. Additionally, network security controls such as web proxies with content filtering and DNS-level protections can provide additional layers of defense against exploitation attempts. Regular security assessments should verify that browser configurations maintain proper security settings and that users are not inadvertently exposed to outdated browser versions that may contain similar vulnerabilities.