CVE-2013-5227 in iOS
Summary
by MITRE
Apple Safari before 6.1.1 and 7.x before 7.0.1 allows remote attackers to bypass the Same Origin Policy and discover credentials by triggering autofill of subframe form fields.
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Analysis
by VulDB Data Team • 02/20/2022
This vulnerability in Apple Safari represents a critical security flaw that undermines the fundamental Same Origin Policy mechanism designed to protect web applications from cross-site scripting attacks. The issue affects Safari versions prior to 6.1.1 and 7.0.1, where attackers can exploit a weakness in the browser's handling of form autofill functionality to bypass security restrictions that normally prevent scripts from accessing data across different origins. The vulnerability specifically targets the interaction between parent and subframe elements, allowing malicious actors to manipulate form field autofill behavior in ways that should not be permitted under standard security protocols.
The technical implementation of this flaw involves the browser's automatic credential filling feature being triggered within nested frame structures. When a web page contains an iframe or subframe that loads content from a different origin, the Safari browser's autofill system can inadvertently expose credential information from the parent frame to the subframe context. This occurs because the browser fails to properly validate the security boundaries between different frame contexts when processing autofill requests, creating an unintended information leakage channel that violates core web security principles. The vulnerability demonstrates a clear failure in the browser's sandboxing mechanisms and access control enforcement.
The operational impact of this vulnerability extends beyond simple credential theft, as it provides attackers with a method to perform sophisticated reconnaissance and credential harvesting attacks. An attacker could construct malicious web pages that load legitimate sites within iframes and then trigger autofill behaviors to extract username and password combinations from users who have saved credentials in Safari. This represents a significant threat to enterprise security environments where users frequently save login information and may unknowingly visit compromised websites that exploit this vulnerability. The attack vector requires minimal user interaction beyond visiting a malicious page, making it particularly dangerous in phishing scenarios and social engineering campaigns.
Organizations should implement immediate mitigations including mandatory browser updates to Safari 6.1.1 or 7.0.1 versions that contain the necessary security patches. Network administrators should consider implementing web application firewalls and content filtering solutions that can detect and block suspicious iframe behaviors. Security teams should also conduct comprehensive user awareness training to educate employees about the risks of visiting untrusted websites and the importance of keeping browser software updated. From a compliance perspective, this vulnerability relates to CWE-200 (Information Exposure) and CWE-352 (Cross-Site Request Forgery) categories, while the attack methodology aligns with ATT&CK techniques involving credential access and privilege escalation through browser-based attacks. The vulnerability highlights the critical importance of maintaining up-to-date browser security patches and demonstrates how seemingly minor functionality flaws can create significant security risks in web applications.