CVE-2026-72279
CriticalCVSS 9.0Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
In the Linux kernel, KVM arm64 (nested mode) mapping of L1 VNCR into host stage-1 did not respect read-only PFNs. The fix caches PFN writability and constrains mapping permissions, also fixing a page leak.
Risk Assessment
This could lead to unauthorized writes to read-only memory, breaking memory isolation and potentially causing memory leaks.
Recommendation
Install the Linux kernel patch for KVM arm64 that respects read-only PFNs when mapping L1 VNCR.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Respect read-only PFN when mapping L1 VNCR KVM currently maps the L1 VNCR into the host stage-1 by relying entirely on the permissions of the guest stage-1. At the same time, it is entirely possible that the backing PFN is read-only (e.g. RO memslot), meaning that the L1 VNCR should use at most a read-only mapping. Cache the writability of the PFN in the VNCR TLB and use it to constrain the resulting fixmap permissions. Promote VNCR permission faults to an SEA in the case where the guest attempts to write to a read-only endpoint. Conveniently, this also plugs a page leak found by Sashiko [*] resulting from the early return for a read-only PFN.