Vulnerability in Linux

CVE-2026-63938

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Check PSC request indices against the actual size of the buffer When processing Page State Change (PSC) requests, validate the PSC buffer against the effective size of the scratch area, which could be less than the maximum size if the guest provided a pointer that isn't exactly at the start of the GHCB shared buffer.

EPSS: 0.002 (8.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

Affected products

  • Linux — versions 9b54e248d2644be71cb394eb85f31ad99e023a05, 6.11, 0

References

Frequently asked questions

What is CVE-2026-63938?
CVE-2026-63938 is a critical-severity vulnerability in Linux. CVSS score: 9.3/10. Published 2026-07-19.
How severe is CVE-2026-63938?
Critical severity. CVSS v3 base score is 9.3 out of 10.