KVM: nSVM: Triple fault if restore host CR3 fails on nested #VMEXIT
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Triple fault if restore host CR3 fails on nested #VMEXIT If loading L1's CR3 fails on a nested #VMEXIT, nested_svm_vmexit() returns an error code that is ignored by most callers, and continues to run L1 with corrupted state. A sane recovery is not possible in this case, and HW behavior is to cause a shutdown. Inject a triple fault instead, and do not return early from nested_svm_vmexit(). Continue cleaning up the vCPU state (e.g. clear pending exceptions), to handle the failure as gracefully as possible. From the APM: Upon #VMEXIT, the processor performs the following actions in order to return to the host execution context: ... if (illegal host state loaded, or exception while loading host state) shutdown else execute first host instruction following the VMRUN Remove the return value of nested_svm_vmexit(), which is mostly unchecked anyway.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.114, 6.18.57, 7.0.4, 7.1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-46032
- 2026-10-03 Alias added: GHSA-rgj9-vx7j-x86j
- 2026-10-16 Fix available: Linux/[email protected], Linux/Linux@b0eb0a8959ac2b808eb11548d002fe1f9b5650cc · CNA
- 2026-10-16 1 new reference · CNA
- 2026-10-21 Fix available: Linux/Linux@2e661773890e6ba6b16064fad961da3dd311be43, Linux/[email protected], Linux/[email protected] +1 · CNA
- 2026-10-21 2 new references · CNA
- 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@e6318570a9b4e137b0b744832b920b38bb069561 · CNA
- 2026-10-30 1 new reference · CNA
- 2026-11-06 CISA SSVC decision points changed
References
Patch 2
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Sources
- CVE-2026-46032 · CVE Program
- CVE-2026-46032 · NVD
- FIRST EPSS
- GHSA-rgj9-vx7j-x86j · GitHub Advisory Database · CC BY 4.0
- CVE-2026-46032 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences