CVE-2017-13877 in iOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 11 is affected. The issue involves the "Sandbox Profiles" component. It allows attackers to determine whether arbitrary files exist via a crafted app.
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Analysis
by VulDB Data Team • 01/20/2020
The vulnerability identified as CVE-2017-13877 represents a significant information disclosure flaw within Apple's iOS sandboxing mechanism that affected versions prior to iOS 11. This weakness resides within the sandbox profiles component, which serves as a critical security feature designed to isolate applications and prevent unauthorized access to system resources. The flaw enables attackers to perform reconnaissance activities by determining the existence of arbitrary files on the device through the exploitation of a crafted malicious application. The vulnerability stems from insufficient validation within the sandbox profile implementation that fails to properly restrict file system access queries.
The technical nature of this vulnerability aligns with CWE-200, which describes improper exposure of sensitive information, and demonstrates how sandboxing mechanisms can be circumvented to gain unauthorized knowledge about the underlying file system structure. Attackers can leverage this weakness by constructing a malicious application that attempts to access files through the sandboxed environment, potentially revealing file paths, directory structures, or even sensitive data about the device's file system organization. The flaw specifically impacts the sandbox profile validation logic, which should normally prevent such enumeration activities but fails to adequately filter or restrict the file system queries.
Operationally, this vulnerability creates a serious risk for iOS devices as it allows attackers to perform reconnaissance activities that could lead to more sophisticated attacks. The ability to determine file existence provides attackers with valuable intelligence about the device's file system layout, potentially revealing the presence of sensitive applications, system files, or user data. This information disclosure could serve as a foundation for subsequent attacks, including privilege escalation attempts or targeted exploitation of specific applications. The impact is particularly concerning given that the vulnerability affects iOS versions before 11, which were widely deployed across numerous devices.
The security implications extend beyond simple file enumeration as this vulnerability demonstrates how sandboxing mechanisms can be bypassed to gain unauthorized knowledge about system resources. From an att&ck framework perspective, this vulnerability maps to techniques involving reconnaissance and privilege escalation, as it enables attackers to gather intelligence about the target environment. The flaw represents a failure in the principle of least privilege enforcement, where the sandbox profile component does not properly isolate application access to prevent unauthorized file system queries. Organizations should consider this vulnerability as part of their broader security posture assessment, particularly when evaluating the effectiveness of application sandboxing implementations. The recommended mitigation involves upgrading to iOS 11 or later versions where Apple has addressed this specific sandbox profile validation issue through enhanced file system access controls and improved sandbox enforcement mechanisms.