CVE-2018-9410 in Android
Summary
by MITRE • 11/20/2024
In analyzeAxes of FontUtils.cpp, there is a possible out of bounds read due to a missing bounds check. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 11/20/2024
The vulnerability identified as CVE-2018-9410 represents a critical out-of-bounds read flaw within the FontUtils.cpp component of a software system. This issue manifests specifically within the analyzeAxes function where proper bounds checking mechanisms are absent, creating a scenario where memory access occurs beyond the allocated buffer boundaries. The vulnerability falls under the category of memory safety issues and is classified as a CWE-129 vulnerability, which represents an "Improper Validation of Array Index" that can lead to unauthorized data access patterns. The flaw exists in the font processing utilities where the application fails to validate array indices before accessing potentially unbounded memory regions.
The technical exploitation of this vulnerability does not require any special privileges or user interaction, making it particularly dangerous as it can be triggered automatically during normal font rendering operations. When the analyzeAxes function processes font data, it accesses memory locations beyond the intended array bounds without proper validation, potentially exposing sensitive information stored in adjacent memory locations. This type of vulnerability aligns with ATT&CK technique T1059.007 which covers "Command and Scripting Interpreter: JavaScript" and can be leveraged in scenarios involving font processing within web browsers or document viewers where JavaScript engines interact with font data structures. The absence of bounds checking creates a predictable access pattern that attackers can exploit to extract information from memory, potentially including stack contents, heap data, or other sensitive system information.
The operational impact of this vulnerability extends beyond simple information disclosure, as it represents a foundational security weakness that could enable more sophisticated attacks. The local information disclosure aspect means that an attacker with minimal privileges could potentially extract confidential data from the application's memory space, including cryptographic keys, user credentials, or other sensitive information. This vulnerability affects applications that process font files, particularly those using the affected font utility library, and could be exploited in web browsers, document processing applications, or any system that renders fonts without proper input validation. The vulnerability's exploitation requires no user interaction, making it particularly concerning for automated attacks or when the software is used in environments where untrusted font data might be processed.
Mitigation strategies for CVE-2018-9410 should focus on implementing comprehensive bounds checking mechanisms within the analyzeAxes function and similar font processing routines. The most effective approach involves adding proper array index validation before any memory access operations, ensuring that all array accesses are within the defined bounds. Security patches should be applied immediately to update the font processing library and eliminate the missing bounds check. Additionally, input validation should be strengthened to prevent malformed font data from reaching the vulnerable function. System administrators should consider implementing application whitelisting and sandboxing measures to limit the potential impact of exploitation. The vulnerability's classification as a CWE-129 issue indicates that defensive programming practices should be enhanced throughout the codebase to prevent similar flaws in other array handling functions, particularly those involving font rendering and processing operations that may be susceptible to similar out-of-bounds memory access patterns.