CVE-2016-4741 in iOS
Summary
by MITRE
The Assets component in Apple iOS before 10 allows man-in-the-middle attackers to block software updates via vectors related to lack of an HTTPS session for retrieving updates.
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Analysis
by VulDB Data Team • 09/16/2022
The vulnerability identified as CVE-2016-4741 affects Apple iOS versions prior to 10 and resides within the Assets component of the operating system. This flaw represents a significant security weakness that undermines the integrity of the software update mechanism. The vulnerability stems from the absence of proper HTTPS session handling during the retrieval of software updates, creating a pathway for malicious actors to intercept and manipulate the update process. The technical implementation fails to establish secure encrypted connections for update downloads, leaving devices susceptible to various forms of network-based attacks.
The core technical flaw manifests in the Assets component's inability to maintain secure HTTPS sessions when communicating with Apple's update servers. This weakness enables man-in-the-middle attackers to position themselves between the iOS device and Apple's infrastructure, effectively intercepting update traffic. The vulnerability operates at the transport layer security level, where the system should enforce secure communication channels but fails to do so properly. Attackers can exploit this gap to block legitimate software updates, potentially leaving devices vulnerable to known exploits while simultaneously preventing users from receiving critical security patches. This represents a violation of the principle of secure communication and proper certificate validation.
The operational impact of this vulnerability extends beyond simple update blocking, as it creates a persistent security risk for affected iOS devices. Users may unknowingly remain on outdated software versions that contain known vulnerabilities, increasing their exposure to malware and other cyber threats. The vulnerability particularly affects enterprise environments where security updates are critical for maintaining compliance and protecting sensitive data. Organizations relying on iOS devices for business operations face potential data breaches and regulatory violations if devices remain vulnerable due to blocked updates. The impact is compounded by the fact that this vulnerability affects multiple iOS versions, requiring widespread remediation efforts across affected deployments.
Mitigation strategies for CVE-2016-4741 primarily involve upgrading to iOS 10 or later versions where Apple has addressed the HTTPS session handling issues. Organizations should implement network monitoring to detect unusual traffic patterns that might indicate update interception attempts. The vulnerability aligns with CWE-319, which addresses the exposure of sensitive information through improper use of network protocols, and relates to ATT&CK technique T1071.004 for application layer protocol usage. Additional protective measures include implementing network security controls such as SSL inspection capabilities and ensuring proper certificate validation procedures are in place. Security teams should also consider deploying endpoint protection solutions that can detect and prevent update tampering attempts, while maintaining awareness of the specific network configurations that might expose devices to this attack vector.