{"cve":"CVE-2026-63938","nvd":{"published":"2026-07-19T16:17:12.323","modified":"2026-10-19T21:17:12.693","status":"Undergoing Analysis","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","score":9.3},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/121d88de56bc5c0ba0ce2f6381af67f948a7e7c1","https://git.kernel.org/stable/c/505a3b94535583e4265360e2621734e355ef263d","https://git.kernel.org/stable/c/5198f70c09a5f6e9e5f5a0a2c6b388f24294b176","https://git.kernel.org/stable/c/75c8d1d7291268b479794fba5808971dc2f5eaf3"],"products":[],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-63938","score":0.00196,"percentile":0.09174,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}