CVE-2025-71227 in Linux
Summary
by MITRE • 02/18/2026
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: don't WARN for connections on invalid channels
It's not clear (to me) how exactly syzbot managed to hit this, but it seems conceivable that e.g. regulatory changed and has disabled a channel between scanning (channel is checked to be usable by cfg80211_get_ies_channel_number) and connecting on the channel later.
With one scenario that isn't covered elsewhere described above, the warning isn't good, replace it with a (more informative) error message.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/22/2026
The vulnerability identified as CVE-2025-71227 resides within the Linux kernel's mac80211 subsystem, which handles wireless networking functionality for IEEE 802.11 devices. This issue specifically addresses a problematic warning condition that occurs during wireless connection establishment processes. The flaw manifests when the kernel encounters connections being attempted on channels that have become invalid due to regulatory changes or other dynamic environmental factors. The warning mechanism, while intended to alert developers to potential issues, actually creates unnecessary system noise and can mask more serious underlying problems that require proper error handling rather than simple warnings.
The technical implementation of this vulnerability stems from the mac80211 subsystem's channel validation process during wireless connection establishment. When a wireless device scans for available networks, it uses cfg80211_get_ies_channel_number to verify channel usability. However, between the scanning phase and the actual connection attempt, regulatory domains may change, causing previously valid channels to become disabled. This temporal gap creates a scenario where the system attempts to establish a connection on a channel that was valid during scanning but has since become invalid, triggering an inappropriate WARN macro instead of proper error handling.
The operational impact of this vulnerability extends beyond simple system logging issues, as it represents a failure in proper error propagation and state management within the wireless subsystem. The problematic WARN macro implementation can lead to confusion during debugging and system monitoring, as it does not provide the appropriate error context that administrators or developers would expect. This behavior can mask legitimate connection failures or regulatory compliance issues that should be handled with proper error codes and logging mechanisms. The vulnerability demonstrates a gap in the kernel's wireless regulatory domain handling and channel validation processes, where the system fails to distinguish between expected operational conditions and genuine error states.
The fix implemented for CVE-2025-71227 addresses this by replacing the inappropriate WARN macro with a more informative error message that properly communicates the channel invalidity condition to the system. This change aligns with security best practices by ensuring that wireless connection failures are properly logged and handled according to established kernel error handling protocols. The solution follows the principle of least privilege and proper error state management, where the system should provide clear diagnostic information rather than generic warnings that may obscure the actual problem. This modification also supports compliance with industry standards such as those outlined in the Common Weakness Enumeration (CWE) categories related to improper error handling and information exposure, while addressing potential attack surface considerations in wireless network management systems. The change ensures that wireless network administrators receive appropriate feedback when regulatory changes affect channel availability, enabling better troubleshooting and system maintenance practices.