CVE-2017-9683 in Android
Summary
by MITRE
In Android for MSM, Firefox OS for MSM, QRD Android, with all Android releases from CAF using the Linux kernel, while flashing a meta image, an integer overflow can occur, if user-defined image offset and size values are too large.
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Analysis
by VulDB Data Team • 01/16/2021
The vulnerability identified as CVE-2017-9683 represents a critical integer overflow condition affecting multiple Android variants and Firefox OS implementations running on Qualcomm MSM hardware platforms. This flaw manifests specifically during the meta image flashing process, where the system processes user-defined offset and size parameters that, when excessively large, trigger arithmetic overflow conditions within the kernel-level flashing utilities. The vulnerability resides in the Linux kernel components used by these mobile operating systems, making it particularly concerning given the widespread adoption of Qualcomm MSM chipsets in Android devices. The integer overflow occurs when the system attempts to calculate memory addresses or buffer boundaries using these user-provided parameters, leading to potential memory corruption scenarios.
The technical implementation of this vulnerability stems from inadequate input validation within the flashing utilities that handle meta image processing. When users or processes provide offset and size values that exceed the maximum representable values for the integer data types used in the calculation logic, the arithmetic operations wrap around unexpectedly. This overflow condition can result in incorrect memory allocation decisions, where the system might allocate insufficient memory or calculate invalid memory addresses. The vulnerability is particularly dangerous because it occurs in the flashing process, which typically runs with elevated privileges and has direct access to low-level system memory. The integer overflow can potentially be exploited to overwrite adjacent memory locations or cause memory corruption that may lead to privilege escalation or system instability.
From an operational impact perspective, this vulnerability creates significant security risks for devices running affected Android and Firefox OS versions. The flashing process is commonly used for system updates, recovery operations, and device provisioning, making this vulnerability exploitable during legitimate system maintenance activities. Attackers could potentially craft malicious meta images with carefully constructed offset and size values to trigger the integer overflow, potentially gaining unauthorized access to system resources or executing arbitrary code. The vulnerability affects all Android releases from the Code_Aurora_Forum (CAF) that utilize the Linux kernel, representing a substantial attack surface across numerous device models and manufacturers. The impact extends beyond simple denial of service, as memory corruption from integer overflow can lead to more severe consequences including system compromise or data exposure.
Mitigation strategies for CVE-2017-9683 should focus on both immediate patching and operational security measures. Device manufacturers and system integrators must ensure that all affected Android and Firefox OS implementations receive appropriate kernel updates that include proper integer overflow checks and input validation for the flashing utilities. The fix should implement bounds checking on user-provided offset and size parameters, ensuring that calculations remain within safe integer ranges before any memory allocation occurs. Additionally, organizations should implement strict validation procedures for meta images used in the flashing process, including automated checks for parameter合理性 and size limitations. From a defensive standpoint, this vulnerability aligns with CWE-191, which describes integer underflow/overflow conditions, and could potentially map to ATT&CK technique T1059 for privilege escalation through system-level code execution. Network security teams should monitor for exploitation attempts during firmware update processes, as this vulnerability could be leveraged in targeted attacks against specific device populations. The mitigation approach should also include implementing secure flashing protocols that prevent arbitrary parameter injection and establish proper access controls for flashing operations, particularly in enterprise environments where device management is critical.