CVE-2016-7623 in iOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 10.2 is affected. Safari before 10.0.2 is affected. The issue involves the "WebKit" component. It allows remote attackers to obtain sensitive information via a blob URL on a web site.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/06/2022
The vulnerability identified as CVE-2016-7623 represents a significant security flaw within Apple's WebKit rendering engine that impacted multiple iOS and Safari versions. This issue specifically affects iOS versions prior to 10.2 and Safari versions prior to 10.0.2, demonstrating the widespread nature of the vulnerability across Apple's ecosystem. The flaw resides within the WebKit component which serves as the core web rendering engine for Apple's browsers and applications, making it a critical attack surface that could potentially compromise user data across numerous devices and platforms. The vulnerability's classification aligns with CWE-200, which addresses "Information Exposure Through Environmental Data," as it enables unauthorized access to sensitive information through improper handling of web resources.
The technical implementation of this vulnerability exploits how WebKit processes blob URLs within web applications, creating an information disclosure channel that remote attackers can leverage without requiring user interaction or authentication. Blob URLs are temporary identifiers that reference binary data stored in memory, typically used for handling file uploads and downloads within web applications. The flaw occurs when these blob URLs are improperly handled or exposed through web pages, allowing attackers to access memory contents that should remain isolated and protected. This type of vulnerability falls under the ATT&CK technique T1059.006 for "Command and Scripting Interpreter: JavaScript", as it involves manipulating JavaScript-based web content to access sensitive information through the browser's memory management system. The exploitation mechanism likely involves crafting malicious web content that can access or enumerate blob URL references, potentially exposing sensitive data such as user credentials, personal information, or application memory contents.
The operational impact of CVE-2016-7623 extends beyond simple information disclosure, as it represents a fundamental flaw in how Apple's web rendering system handles temporary data references. Attackers could potentially use this vulnerability to access sensitive information that was previously isolated within the browser's memory space, compromising user privacy and data security. The vulnerability affects not just individual users but could be leveraged at scale through malicious websites that could be accessed by unsuspecting users, making it particularly dangerous in phishing campaigns or targeted attacks. This type of information exposure could enable further attacks such as credential theft, session hijacking, or even privilege escalation within affected applications that rely on WebKit for content rendering. The vulnerability's impact is amplified by the fact that it affects widely used Apple products including iPhones, iPads, and Mac systems running the affected software versions, creating a substantial attack surface that could be exploited by threat actors without requiring specialized tools or extensive knowledge of the target environment. Organizations and individuals using affected Apple products were at risk of having their sensitive data exposed through this vulnerability, which could have cascading effects on personal privacy, corporate security, and overall user trust in Apple's security infrastructure.
Apple's response to this vulnerability involved releasing security updates for iOS 10.2 and Safari 10.0.2, which addressed the information disclosure issue within the WebKit component. The fix likely involved implementing proper access controls and memory management for blob URLs, ensuring that these temporary identifiers cannot be accessed or enumerated by unauthorized web content. Users were strongly advised to update their systems immediately to protect against potential exploitation, as the vulnerability could be exploited remotely without any user interaction, making it particularly dangerous in automated attack scenarios. The vulnerability serves as a reminder of the importance of proper memory management in web browser components and the critical need for regular security updates to protect against information disclosure vulnerabilities that could compromise user data and system integrity. Organizations implementing security controls should monitor for affected systems and ensure timely deployment of patches to prevent exploitation of this type of vulnerability, which could be used as a stepping stone for more sophisticated attacks within targeted environments.