CVE-2026-63938: Linux

Critical severity, CVSS 9.3. EPSS: 0.2% chance of exploitation in the next 30 days.

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.

Affected products

• Linux Linux: from 6.11, before 6.12.93 (fixed in 6.12.93); from 6.13, before 6.18.35 (fixed in 6.18.35); from 6.19, before 7.0.12 (fixed in 7.0.12)

Published 2026-07-19. Last modified 2026-07-27.