CVEvulnerability
CVE-2026-63937
8.8 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2026-07-19
- Last modified
- 2026-10-27
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 8.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- Weaknesses
- CWE-367
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.
Affected configurations
• linux linux kernel (>= 6.11 < 6.12.93)
• linux linux kernel (>= 6.13 < 6.18.35)
• linux linux kernel (>= 6.19 < 7.0.12)
• linux linux kernel 7.1
Related
Weakness · CWE (1)
- CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition weakness
References
- https://git.kernel.org/stable/c/b1dfaa6f7a957726a6800135be3659fbe4bbf2a4 Patch
- https://git.kernel.org/stable/c/bd232801ef1d1fd985d2d4ca3cd1d888303ca86f Patch
- https://git.kernel.org/stable/c/c8cc238093ca6c99267032f6cfe78f59389f3157 Patch
- https://git.kernel.org/stable/c/edbbe88f83b524434974e84808d3093199d67c24 Patch