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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63937 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/b1dfaa6f7a957726a6800135be3659fbe4bbf2a4 kernel.org
https://git.kernel.org/stable/c/bd232801ef1d1fd985d2d4ca3cd1d888303ca86f kernel.org
https://git.kernel.org/stable/c/c8cc238093ca6c99267032f6cfe78f59389f3157 kernel.org
https://git.kernel.org/stable/c/edbbe88f83b524434974e84808d3093199d67c24 kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63937
NVD Published Date:
07/19/2026
NVD Last Modified:
07/20/2026
Source:
kernel.org