{"id":"CVE-2026-89921","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Zero initialize data structures for inject_pfault_token\n\n__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of\nthe on-stack struct kvm_s390_i…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Zero initialize data structures for inject_pfault_token\n\n__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of\nthe on-stack struct kvm_s390_i…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 383d0b050106abecb82f43101cac94fa423af5cd < 9b046de62b8098af6e2ba820b125ec9dc5f162c8","Linux >= 383d0b050106abecb82f43101cac94fa423af5cd < 134f235e0e8de54611a72d3cc3f63e5f31246baa","Linux >= 383d0b050106abecb82f43101cac94fa423af5cd < 4e2c7f7cbc27418f9a290399b986c1b85ff93b90","Linux 3.19"],"published":"2026-09-16","updated":"2026-09-16","sourceUpdated":"2026-09-16T11:17:01.173","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89921","references":[{"url":"https://git.kernel.org/stable/c/134f235e0e8de54611a72d3cc3f63e5f31246baa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4e2c7f7cbc27418f9a290399b986c1b85ff93b90","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9b046de62b8098af6e2ba820b125ec9dc5f162c8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-16T10:53:53.972Z","epss":0.00198,"epssPercentile":0.09834,"slug":"CVE-2026-89921","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Zero initialize data structures for inject_pfault_token\n\n__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of\nthe on-stack struct kvm_s390_irq but the full ext substructure is copied\ninto the cpu local variable on inject. ext_params and pad contain stale\nstack values.\n\nInterrupt delivery only uses ext_params2, so nothing leaks to the guest,\nbut a host user can use the migration ioctls to get to the data.\n\nFix by zero-initializing the irq struct.\nDo the same for the inti data structure.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}