CVE-2021-22463 in HarmonyOS
Summary
by MITRE • 10/28/2021
A component of the HarmonyOS has a Use After Free vulnerability . Local attackers may exploit this vulnerability to cause Kernel Information disclosure.
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Analysis
by VulDB Data Team • 11/01/2021
The CVE-2021-22463 vulnerability represents a critical use after free flaw within the HarmonyOS operating system component. This vulnerability falls under the CWE-416 category, which specifically addresses use after free conditions where memory is accessed after it has been freed, potentially leading to unpredictable behavior and security exploitation. The flaw exists within the kernel-level components of HarmonyOS, making it particularly dangerous as it operates at the core of the operating system's functionality. Local attackers can exploit this vulnerability by manipulating memory allocation and deallocation patterns to trigger the use after free condition, which then allows them to gain access to kernel memory structures and potentially extract sensitive information.
The technical implementation of this vulnerability involves improper memory management within the HarmonyOS kernel subsystem. When certain kernel functions process memory allocations and deallocations, they fail to properly validate or track memory references after freeing allocated blocks. This creates a window where malicious code can overwrite freed memory with controlled data, leading to information disclosure attacks. The vulnerability specifically targets kernel memory regions that contain sensitive information such as system configuration data, security tokens, or cryptographic keys. The exploitation process typically involves crafting specific memory operations that cause the kernel to free memory blocks while maintaining references to them, then manipulating the freed memory to extract kernel information through memory read operations.
The operational impact of CVE-2021-22463 extends beyond simple information disclosure, as it creates a potential pathway for more sophisticated attacks within the HarmonyOS environment. Attackers who successfully exploit this vulnerability can gain insights into kernel memory layouts, system configurations, and potentially identify other exploitable weaknesses within the operating system. This information disclosure can serve as a foundation for privilege escalation attacks, where the leaked kernel information enables attackers to craft more targeted exploits against other system components. The local nature of this vulnerability means that attackers must already have access to the system, but the privilege escalation potential makes it particularly dangerous in environments where physical access or user-level compromise is possible.
Mitigation strategies for CVE-2021-22463 should focus on implementing robust memory management practices within the HarmonyOS kernel. System administrators should ensure that all HarmonyOS devices are updated with the latest security patches provided by Huawei, as the vulnerability has been addressed through proper memory management fixes and validation checks. The implementation of kernel memory protection mechanisms such as stack canaries, memory sanitizers, and heap metadata validation can help prevent exploitation attempts. Additionally, organizations should consider implementing runtime monitoring solutions that can detect anomalous memory access patterns and potential use after free conditions. Security teams should also conduct regular vulnerability assessments and penetration testing to identify similar memory management issues within the operating system. The ATT&CK framework categorizes this vulnerability under T1068 for locally exploited privileges and T1005 for data from local system, highlighting the multi-faceted nature of the threat landscape this vulnerability creates.