CVE-2026-89921. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-89921?
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Zero initialize data structures for inject_pfault_token
__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of the on-stack struct kvm_s390_irq but the full ext substructure is copied into the cpu local variable on inject. ext_params and pad contain stale stack values.
Interrupt delivery only uses ext_params2, so nothing leaks to the guest, but a host user can use the migration ioctls to get to the data.
Fix by zero-initializing the irq struct. Do the same for the inti data structure.