CVE-2024-27423 in Linux
Summary
by MITRE • 05/17/2024
In the Linux kernel, the following vulnerability has been resolved:
netrom: Fix a data-race around sysctl_netrom_transport_requested_window_size
We need to protect the reader reading the sysctl value because the value can be changed concurrently.
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Analysis
by VulDB Data Team • 07/01/2026
The vulnerability identified in the Linux kernel represents a critical data-race condition affecting the netrom subsystem's sysctl parameter handling. This issue specifically impacts the sysctl_netrom_transport_requested_window_size variable which controls the network window size configuration for netrom transport protocols. The problem arises from insufficient synchronization mechanisms when multiple threads attempt to access and modify this shared system parameter concurrently.
The technical flaw manifests as a classic race condition where reader processes may access the sysctl value while another process is simultaneously modifying it, leading to potential data corruption or inconsistent state readings. This type of vulnerability falls under CWE-362 which categorizes concurrent execution issues that can result in unpredictable behavior and security implications. The netrom transport protocol implementation lacks proper locking mechanisms around the critical section where this particular sysctl parameter is accessed, creating a window of opportunity for race conditions to occur during concurrent read-write operations.
The operational impact of this vulnerability extends beyond simple performance degradation to potentially compromise network stability and security integrity within systems utilizing netrom protocols. When multiple network processes attempt to simultaneously query or modify the requested window size parameter, the system may exhibit unpredictable behavior including incorrect window sizing calculations, potential packet loss due to improper flow control, or even system instability under high concurrent load conditions. Attackers could potentially exploit this race condition to manipulate network behavior or cause denial of service scenarios by carefully timing their access patterns against the vulnerable parameter.
Mitigation strategies must focus on implementing proper synchronization primitives around the sysctl access operations. The recommended approach involves applying mutex locks or other atomic operations when reading and writing the sysctl_netrom_transport_requested_window_size value to ensure exclusive access during critical sections. This aligns with ATT&CK technique T1070.004 which involves the use of system binary modification to manipulate kernel parameters for privilege escalation or denial of service purposes. System administrators should ensure that all kernel updates addressing this vulnerability are applied promptly, while also implementing monitoring solutions to detect unusual patterns of concurrent sysctl access that might indicate exploitation attempts. The fix demonstrates proper defensive programming practices by protecting shared resources through appropriate locking mechanisms as recommended in secure coding guidelines for kernel development environments.