CVE-2025-71229: 
Linux Kernel vulnerability analysis and mitigation

CVE-2025-71229 is an alignment fault vulnerability in the Linux kernel's rtw88 WiFi driver, specifically in the rtw_core_enable_beacon() function, which performs a 4-byte read from a non-4-byte-aligned memory address, causing a kernel panic on systems that enforce strict memory alignment (notably ARM-based architectures). It affects Linux kernel versions 6.5.x through 6.6.124, 6.7.x through 6.12.71, 6.13.x through 6.18.10, and 6.19.0, as well as Microsoft Azure Linux kernel 6.6.121.1-1. The vulnerability was published on February 18, 2026, and has a CVSS v3.1 base score of 5.5 (Medium) (Red Hat Advisory, Red Hat Bugzilla, Microsoft MSRC).

The root cause is an improper memory access (CWE-119/misaligned access) in rtw_core_enable_beacon() within the rtw88_core kernel module, where a 32-bit read (rtw_pci_read32) is performed on an address (ffff8000827e0522) that is not aligned to a 4-byte boundary. On ARM64 systems with strict alignment enforcement, this triggers an alignment fault (ESR 0x0000000096000021, FSC 0x21) and results in a kernel Oops/panic. The fix replaces the 4-byte read/write operations with 1-byte operations to avoid the alignment requirement. The crash occurs in the context of the rtw_c2h_work workqueue during wireless beacon/channel-switch processing, affecting RTL8822C and RTL8822CE chipsets (Red Hat Bugzilla).

Successful triggering of this vulnerability results in a kernel panic, causing an immediate system crash and denial of service. The impact is limited to availability — there is no confidentiality or integrity impact. Systems running ARM-based hardware (such as the FriendlyElec NanoPC-T6) with RTL8822C/RTL8822CE WiFi adapters and affected kernel versions are at risk of unexpected reboots during normal wireless operations, particularly during beacon processing or channel switching (Red Hat Advisory, Red Hat Bugzilla).

• Logs: Kernel logs (dmesg, /var/log/kern.log) showing Internal error: Oops: 0000000096000021 with a call trace involving rtw_pci_read32, rtw_core_enable_beacon, rtw_hw_scan_chan_switch, or rtw_c2h_work.
• Logs: Messages referencing Unable to handle kernel paging request at virtual address with FSC 0x21: alignment fault and modules rtw88_8822ce, rtw88_8822c, rtw88_pci, or rtw88_core in the linked modules list.
• System Behavior: Unexpected system reboots or kernel panics on ARM-based systems equipped with RTL8822C/RTL8822CE WiFi adapters during wireless activity.

Update the Linux kernel to a patched version: 6.6.125+, 6.12.72+, 6.18.11+, or 6.19.1+. Microsoft Azure Linux users should apply the latest kernel security updates addressing this CVE. If immediate patching is not feasible, consider disabling the rtw88 driver (modprobe -r rtw88_8822ce rtw88_8822c rtw88_pci rtw88_core) or replacing affected RTL8822C/RTL8822CE WiFi hardware with an adapter using a different driver. Monitor systems for unexpected reboots that may indicate the fault is being triggered (Red Hat Advisory, Microsoft MSRC, Red Hat Bugzilla).