CVE-2026-63937
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.14% probability · 3th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-367
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS 0.1% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://git.kernel.org/stable/c/b1dfaa6f7a957726a6800135be3659fbe4bbf2a4Patch
- https://git.kernel.org/stable/c/bd232801ef1d1fd985d2d4ca3cd1d888303ca86fPatch
- https://git.kernel.org/stable/c/c8cc238093ca6c99267032f6cfe78f59389f3157Patch
- https://git.kernel.org/stable/c/edbbe88f83b524434974e84808d3093199d67c24Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.