CVE-2026-63938
Full vulnerability record from the local CVENow database.
Description
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.
Severity
CRITICAL
CVSS score
9.3
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 16:17:12.323000
Last modified
2026-10-27 13:36:28.417000
View original CVE JSON
{
"id": "CVE-2026-63938",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-19T16:17:12.323",
"lastModified": "2026-10-27T13:36:28.417",
"vulnStatus": "Analyzed",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Check PSC request indices against the actual size of the buffer\n\nWhen processing Page State Change (PSC) requests, validate the PSC buffer\nagainst the effective size of the scratch area, which could be less than\nthe maximum size if the guest provided a pointer that isn't exactly at the\nstart of the GHCB shared buffer."
}
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"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
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