In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix AArch32 DBGBXVR<n> handling The consolidation of the breakpoint… (CVE-2026-98469)

The Linux kernel's KVM arm64 module had a vulnerability in handling the AArch32 DBGBXVR<n> register due to a consolidation of breakpoint and watchpoint register accessors. The DBGBXVR<n> register was switched from trap_bvr() to trap_dbg_wb_reg(), which only handled Op2 values 4 through 7. Since DBGBXVR<n> uses Op2 value 1, this caused a KVM_BUG_ON() failure, marking the virtual machine as dead. The fix maps Op2 1 to dbg_bvr[] alongside Op2 4, restoring the previous behavior and preventing VM crashes.

An AArch32 guest accessing the DBGBXVR<n> register in the affected KVM arm64 implementation would trigger a kernel bug check (KVM_BUG_ON()), causing the virtual machine to be terminated unexpectedly. This results in denial of service for the affected VM.

A fix has been applied in the Linux kernel to correctly handle the DBGBXVR<n> register access in KVM arm64. Users should update to the fixed kernel version once available. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.