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.

EPSS

0.2% chance of exploitation in the next 30 days; higher than 10% of CVEs (scores of 2026-10-25)

Published

2026-09-16

Modified

2026-10-21

Record from

the NVD, synced 2026-10-22

References

• https://git.kernel.org/stable/c/134f235e0e8de54611a72d3cc3f63e5f31246baa
• https://git.kernel.org/stable/c/4e2c7f7cbc27418f9a290399b986c1b85ff93b90
• https://git.kernel.org/stable/c/9b046de62b8098af6e2ba820b125ec9dc5f162c8
• https://git.kernel.org/stable/c/ab1a8a3c9971200938093370da4c67d4427c25f2
• https://git.kernel.org/stable/c/b8abc760fa18a389319d977834a30550b3ec18e8

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