CVE-2021-47255
Description
In the Linux kernel, the following vulnerability has been resolved: kvm: LAPIC: Restore guard to prevent illegal APIC register access Per the SDM, "any access that touches bytes 4 through 15 of an APIC register may cause undefined behavior and must not be executed." Worse, such an access in kvm_lapic_reg_read can result in a leak of kernel stack contents. Prior to commit 01402cf81051 ("kvm: LAPIC: write down valid APIC registers"), such an access was explicitly disallowed. Restore the guard that was removed in that commit.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-47255
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2021-47255.html
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 5.10.46-1 |
| debian | bullseye | fixed | 5.10.46-1 |
| debian | forky | fixed | 5.10.46-1 |
| debian | sid | fixed | 5.10.46-1 |
| debian | trixie | fixed | 5.10.46-1 |
References
Verify integrity in audit chain (admin only). AS-IS.