CVE-2015-7036 in iOS
Summary
by MITRE
The fts3_tokenizer function in SQLite, as used in Apple iOS before 8.4 and OS X before 10.10.4, allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a SQL command that triggers an API call with a crafted pointer value in the second argument.
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Analysis
by VulDB Data Team • 04/18/2018
The vulnerability identified as CVE-2015-7036 represents a critical buffer overflow condition within SQLite's full-text search implementation, specifically affecting Apple's mobile and desktop operating systems. This flaw exists in the fts3_tokenizer function which processes text search operations and handles user-provided input through SQL commands. The vulnerability stems from insufficient validation of pointer values passed as the second argument to the API call, creating a pathway for malicious actors to manipulate memory operations. The issue affects versions of iOS prior to 8.4 and OS X prior to 10.10.4, indicating a widespread impact across Apple's ecosystem where SQLite is extensively utilized for database operations and text search functionalities.
The technical exploitation of this vulnerability occurs when a remote attacker crafts a malicious SQL command that specifically targets the fts3_tokenizer function. The flaw manifests when the second argument to the API call contains a crafted pointer value that, upon processing, causes the application to dereference invalid memory locations. This memory corruption can lead to two primary outcomes: arbitrary code execution allowing attackers to run malicious software with the privileges of the affected application, or denial of service through application crashes that disrupt normal system operations. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, where the improper handling of input parameters creates opportunities for memory corruption attacks. The attack vector is particularly concerning because it operates over remote network connections, enabling attackers to exploit the vulnerability without physical access to the target device.
The operational impact of CVE-2015-7036 extends beyond simple application instability, as it creates potential entry points for more sophisticated attacks within Apple's ecosystem. Mobile devices running affected iOS versions become vulnerable to remote exploitation through various attack surfaces including web browsers, email clients, and other applications that utilize SQLite for text search capabilities. The vulnerability's presence in core operating system components means that successful exploitation could compromise the entire device, potentially leading to data theft, persistent backdoor installation, or complete system takeover. This aligns with ATT&CK technique T1059.007 for command and scripting interpreter and T1068 for exploit for privilege escalation, as the vulnerability enables attackers to execute arbitrary code with elevated privileges. The widespread adoption of SQLite in Apple's applications means that numerous legitimate user interfaces could serve as attack vectors, increasing the attack surface significantly.
Mitigation strategies for CVE-2015-7036 primarily focus on immediate system updates and operational security measures. Apple addressed this vulnerability through the release of iOS 8.4 and OS X 10.10.4 updates, which included patches to the SQLite implementation that properly validate pointer arguments to the fts3_tokenizer function. Organizations should prioritize immediate deployment of these security patches across all affected systems to eliminate the exploitability of this vulnerability. Additionally, network administrators should implement monitoring solutions to detect suspicious SQL command patterns that might indicate attempts to exploit this vulnerability, particularly in environments where SQLite databases are actively used. The vulnerability's characteristics align with defensive techniques described in ATT&CK framework under T1566 for credential access and T1070 for indicator removal, as organizations must implement comprehensive monitoring and response procedures to detect and remediate exploitation attempts. Given the severity of the vulnerability, security teams should also consider implementing application whitelisting controls and restricting database access privileges to minimize potential damage from successful exploitation attempts.