CVE-2026-63937 — KVM: SEV: Use READ_ONCE() when reading entries/indices from PSC buffer
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Use READ_ONCE() when reading entries/indices from PSC buffer Use READ_ONCE() when reading entries…
Published: 2026-07-19 · CVSS: 8.8 · CVSS 3.1
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Use READ_ONCE() when reading entries/indices from PSC buffer Use READ_ONCE() when reading entries/indices from the guest-accessible Page State Change buffer to defend against TOCTOU bugs. Don't bother with READ_ONCE()/WRITE_ONCE() for cases where KVM is writing (and not consuming the result!), as the guest isn't supposed to touch the buffer while it's being processed. I.e. using READ_ONCE() is all about protecting against misbehaving guests.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7