CVE-2017-2396 in tvOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 10.3 is affected. Safari before 10.1 is affected. tvOS before 10.2 is affected. The issue involves the "WebKit" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site.
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Analysis
by VulDB Data Team • 11/22/2022
The vulnerability identified as CVE-2017-2396 represents a critical memory corruption flaw within Apple's WebKit rendering engine that affected multiple Apple operating systems including iOS versions prior to 10.3, Safari versions before 10.1, and tvOS versions before 10.2. This weakness resides in the core web browsing component responsible for processing and rendering web content, making it a prime target for remote exploitation by malicious actors. The vulnerability stems from inadequate input validation and memory management within WebKit's JavaScript engine, creating opportunities for attackers to craft malicious web pages that can trigger buffer overflows or use-after-free conditions in memory structures.
The technical nature of this vulnerability places it squarely within CWE-125, which describes out-of-bounds read conditions, and CWE-122, which covers buffer overflow vulnerabilities. Attackers can leverage this flaw by hosting malicious web content on compromised websites or through phishing campaigns that direct victims to exploit the memory corruption issue. When a user navigates to a crafted webpage, the malicious code can manipulate memory pointers or corrupt heap structures, leading to arbitrary code execution capabilities or predictable application crashes. The remote nature of the attack means that users do not need to interact with the malicious content beyond simply loading the webpage, making the vulnerability particularly dangerous in real-world scenarios where users frequently browse the internet.
The operational impact of CVE-2017-2396 extends beyond simple denial of service conditions to encompass full system compromise capabilities that align with ATT&CK technique T1059.1001 for command and scripting interpreter. Successful exploitation could enable attackers to execute arbitrary code with the privileges of the Safari process, potentially leading to complete system compromise depending on the target environment. Mobile device users are particularly at risk since iOS devices lack the traditional desktop security mitigations that might prevent exploitation, and the vulnerability affects the browser component that users interact with most frequently. Organizations and individuals face significant risk from this vulnerability as it allows for persistent threats through web-based attack vectors that can bypass traditional network security controls.
Mitigation strategies for CVE-2017-2396 primarily focus on immediate patching of affected systems to upgrade to supported versions of iOS, Safari, and tvOS that contain the necessary WebKit security fixes. Apple released iOS 10.3, Safari 10.1, and tvOS 10.2 updates specifically addressing this vulnerability, making timely system updates the most effective defense mechanism. Network administrators should implement web content filtering solutions to block access to known malicious domains and consider deploying sandboxing technologies to limit the potential impact of successful exploitation attempts. Security monitoring should include detection of unusual browser behavior patterns and memory access anomalies that might indicate exploitation attempts. Additionally, user education programs should emphasize the importance of avoiding untrusted websites and maintaining current software versions to protect against this and similar web-based vulnerabilities that exploit rendering engine flaws.