CVE-2022-3107 in Linux
Summary
by MITRE • 12/15/2022
An issue was discovered in the Linux kernel through 5.16-rc6. netvsc_get_ethtool_stats in drivers/net/hyperv/netvsc_drv.c lacks check of the return value of kvmalloc_array() and will cause the null pointer dereference.
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Analysis
by VulDB Data Team • 03/05/2025
The vulnerability identified as CVE-2022-3107 represents a critical null pointer dereference flaw within the Linux kernel version 5.16-rc6 and earlier. This issue resides in the hypervisor network virtualization driver component known as netvsc, specifically within the netvsc_get_ethtool_stats function located in the drivers/net/hyperv/netvsc_drv.c file. The vulnerability manifests when the function fails to properly validate the return value of the kvmalloc_array() memory allocation routine, creating a potential pathway for system instability and denial of service conditions.
The technical root cause of this vulnerability stems from inadequate error handling within the network virtualization driver code. When kvmalloc_array() is invoked to allocate memory for ethtool statistics collection, the function does not verify whether the allocation was successful before proceeding with subsequent operations. This oversight allows the code to continue execution with a null pointer reference, ultimately leading to a kernel panic or system crash when the null pointer is dereferenced during statistics retrieval operations. The flaw specifically impacts systems utilizing Hyper-V hypervisor virtualization environments where the netvsc driver is employed for network communication between guest operating systems and the hypervisor.
The operational impact of CVE-2022-3107 extends beyond simple system instability, potentially enabling remote attackers to cause denial of service conditions in virtualized environments. Systems running affected Linux kernel versions within Hyper-V virtual machines become vulnerable to exploitation, particularly in cloud computing scenarios where virtualization is extensively used. The vulnerability can be triggered through normal network operations when ethtool commands are executed against network interfaces managed by the netvsc driver, making it particularly concerning for production environments where monitoring and management tools regularly query network statistics. This weakness aligns with CWE-476, which specifically addresses null pointer dereference vulnerabilities in software systems.
From a threat modeling perspective, this vulnerability demonstrates characteristics consistent with attack patterns documented in the MITRE ATT&CK framework under the T1499 category for network denial of service attacks. The flaw provides an avenue for adversaries to potentially disrupt network services in virtualized environments, affecting availability of critical infrastructure components. The vulnerability's impact is particularly severe in cloud service provider environments where multiple virtual machines share underlying physical hardware, as a single compromised guest could potentially affect the entire host system's stability. Organizations utilizing Linux-based virtual machines in Hyper-V environments must prioritize patching this vulnerability to maintain system integrity and prevent potential exploitation for more sophisticated attacks.
Mitigation strategies for CVE-2022-3107 primarily focus on kernel version updates and system hardening measures. The most effective solution involves upgrading to Linux kernel versions 5.16 or later where the vulnerability has been addressed through proper error handling implementation. System administrators should also implement monitoring solutions to detect unusual network statistics retrieval patterns that might indicate exploitation attempts. Additional defensive measures include restricting access to ethtool commands and implementing proper network segmentation to limit potential attack surfaces. The fix implemented in the patched kernel versions ensures that the return value from kvmalloc_array() is properly validated before proceeding with subsequent memory operations, preventing the null pointer dereference condition that previously led to system instability.