CVE-2012-4221 in Android
Summary
by MITRE
Integer overflow in diagchar_core.c in the Qualcomm Innovation Center (QuIC) Diagnostics (aka DIAG) kernel-mode driver for Android 2.3 through 4.2 allows attackers to execute arbitrary code or cause a denial of service via an application that uses crafted arguments in a local diagchar_ioctl call.
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Analysis
by VulDB Data Team • 08/11/2024
The vulnerability identified as CVE-2012-4221 represents a critical integer overflow flaw within the Qualcomm Innovation Center QuIC Diagnostics kernel-mode driver component of Android operating systems. This vulnerability specifically affects Android versions 2.3 through 4.2 and resides in the diagchar_core.c source file which implements the diagnostic character device interface. The flaw manifests when a local application invokes the diagchar_ioctl system call with crafted arguments that trigger an integer overflow condition during kernel memory operations. Such vulnerabilities fall under the CWE-190 category of Integer Overflow or Wraparound, which represents a fundamental weakness in input validation and arithmetic operations within kernel space code.
The technical exploitation of this vulnerability occurs through a carefully constructed ioctl call that manipulates integer values in a way that causes arithmetic overflow during memory allocation or buffer operations. When the kernel driver processes these malformed arguments, the integer overflow can result in improper memory calculations that may lead to buffer overflows, memory corruption, or other exploitable conditions. The kernel-mode nature of the driver means that successful exploitation would grant attackers elevated privileges equivalent to the kernel itself, potentially enabling complete system compromise. This vulnerability directly maps to ATT&CK technique T1068 which describes the exploitation of vulnerabilities to gain elevated privileges, and T1059 which covers the use of command and scripting interpreters for execution.
The operational impact of this vulnerability extends beyond simple privilege escalation as it creates multiple attack vectors for adversaries. Local applications can leverage this flaw to either execute arbitrary code with kernel-level privileges or cause a denial of service condition that renders the device unusable. The persistent nature of this vulnerability across multiple Android versions indicates a fundamental design flaw in the driver implementation that was not properly addressed in the affected releases. This makes the vulnerability particularly dangerous as it affects a broad range of devices and provides attackers with a reliable method for gaining root access. The integer overflow condition specifically targets memory management operations within the diagnostic driver, making it a prime target for exploitation in mobile device environments where kernel-level access provides complete control over system resources.
Mitigation strategies for CVE-2012-4221 should prioritize immediate patching of affected Android versions through official security updates from device manufacturers and Google. Organizations should implement robust application whitelisting policies to prevent unauthorized applications from invoking diagnostic interfaces, particularly in enterprise environments where device security is paramount. The vulnerability demonstrates the importance of kernel space input validation and proper integer arithmetic handling in mobile operating systems, as highlighted by industry standards such as the OWASP Mobile Security Project recommendations for secure mobile application development. System administrators should also consider implementing monitoring solutions that can detect unusual ioctl call patterns or memory allocation behaviors that may indicate exploitation attempts. Device vendors should conduct thorough security reviews of kernel drivers and implement proper bounds checking and overflow detection mechanisms to prevent similar vulnerabilities from being introduced in future releases.