CVE-2021-43056: Fedoraproject Fedora

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

An issue was discovered in the Linux kernel for powerpc before 5.14.15. It allows a malicious KVM guest to crash the host, when the host is running on Power8, due to an arch/powerpc/kvm/book3s_hv_rmhandlers.S implementation bug in the handling of the SRR1 register values.

Affected products

• Fedoraproject Fedora: version 33 only; version 34 only; version 35 only
• Linux Linux Kernel: from 5.2, before 5.4.15 (fixed in 5.4.15)

Published 2021-10-28. Last modified 2026-06-17.