CVE-2024-27425 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_acknowledge_delay
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 • 07/21/2025
The vulnerability identified in the Linux kernel represents a classic data race condition affecting the netrom subsystem's sysctl parameter management. This issue specifically impacts the sysctl_netrom_transport_acknowledge_delay variable which controls acknowledgment delay settings within the netrom networking protocol implementation. The problem arises from insufficient synchronization mechanisms when multiple threads attempt to access and modify this critical system parameter simultaneously.
The technical flaw manifests as a race condition where concurrent read and write operations on the sysctl_netrom_transport_acknowledge_delay value create unpredictable behavior and potential system instability. When one thread reads the value while another modifies it, the reader may observe an inconsistent or partially updated state, leading to incorrect protocol behavior. This type of vulnerability falls under CWE-362 which specifically addresses race conditions in concurrent programming environments where multiple threads access shared resources without proper synchronization.
The operational impact of this vulnerability extends beyond simple data inconsistency issues. Network communication stability could be compromised as the acknowledgment delay settings directly affect how network packets are handled and acknowledged within the netrom protocol stack. Malicious actors could potentially exploit this race condition to disrupt network services or create denial-of-service scenarios by carefully timing concurrent access attempts to manipulate the sysctl value during critical network operations.
This vulnerability aligns with ATT&CK technique T1499.001 which involves network disruption through resource exhaustion or manipulation of system parameters. The fix implemented addresses this by introducing proper locking mechanisms around the sysctl value access, ensuring that readers must wait for writers to complete their modifications before accessing the parameter. The solution follows established best practices for concurrent programming in kernel space where shared variables requiring atomic access must be protected using appropriate synchronization primitives such as mutexes or spinlocks.
The resolution demonstrates the importance of proper kernel-level synchronization when managing system parameters that control critical network behavior. This fix prevents potential security implications that could arise from inconsistent parameter values during active network operations, maintaining the integrity of the netrom transport layer and ensuring predictable network performance across concurrent access scenarios.