{"id":"CVE-2026-68454","state":"PUBLISHED","title":"KVM: s390: pci: Fix handling of AIF enable without AISB","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: pci: Fix handling of AIF enable without AISB\n\nWhen a guest seeks to register IRQs without a summary bit specified,\nensure that the associated GAITE then stores 0 for the guest AISB\nlocation instead of virt_to_phys(page_address(NULL)).","publishedAt":"2026-08-13T13:59:57.209Z","updatedAt":"2026-10-19T21:09:11.404Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"f887df91826e72b570c5e9298e66dd929f09edde","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"3ef3190e30601b2688bdc64169b938b8d7f42010","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"d48b9b096d11e31690c0a4988f65f21b64c01b2a","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"df72596278b0e22dac5ef2881e9221a3a2c4ed11","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"124a3769c43713a11a93a821b313e61ad5110cb8","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"3e3aa6da87d30a0064a17b836685cd43c90a3572","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/pci.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/pci.c"]}],"references":["https://git.kernel.org/stable/c/f887df91826e72b570c5e9298e66dd929f09edde","https://git.kernel.org/stable/c/3ef3190e30601b2688bdc64169b938b8d7f42010","https://git.kernel.org/stable/c/d48b9b096d11e31690c0a4988f65f21b64c01b2a","https://git.kernel.org/stable/c/df72596278b0e22dac5ef2881e9221a3a2c4ed11","https://git.kernel.org/stable/c/124a3769c43713a11a93a821b313e61ad5110cb8","https://git.kernel.org/stable/c/3e3aa6da87d30a0064a17b836685cd43c90a3572"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/68xxx/CVE-2026-68454.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68454","state":"PUBLISHED","datePublished":"2026-08-13T13:59:57.209Z","dateUpdated":"2026-10-19T21:09:11.404Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-30T09:28:09.395Z"},"containers":{"cna":{"title":"KVM: s390: pci: Fix handling of AIF enable without AISB","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: pci: Fix handling of AIF enable without AISB\n\nWhen a guest seeks to register IRQs without a summary bit specified,\nensure that the associated GAITE then stores 0 for the guest AISB\nlocation instead of virt_to_phys(page_address(NULL))."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"f887df91826e72b570c5e9298e66dd929f09edde","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"3ef3190e30601b2688bdc64169b938b8d7f42010","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"d48b9b096d11e31690c0a4988f65f21b64c01b2a","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"df72596278b0e22dac5ef2881e9221a3a2c4ed11","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"124a3769c43713a11a93a821b313e61ad5110cb8","versionType":"git"},{"version":"3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc","status":"affected","lessThan":"3e3aa6da87d30a0064a17b836685cd43c90a3572","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/pci.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/s390/kvm/pci.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/f887df91826e72b570c5e9298e66dd929f09edde"},{"url":"https://git.kernel.org/stable/c/3ef3190e30601b2688bdc64169b938b8d7f42010"},{"url":"https://git.kernel.org/stable/c/d48b9b096d11e31690c0a4988f65f21b64c01b2a"},{"url":"https://git.kernel.org/stable/c/df72596278b0e22dac5ef2881e9221a3a2c4ed11"},{"url":"https://git.kernel.org/stable/c/124a3769c43713a11a93a821b313e61ad5110cb8"},{"url":"https://git.kernel.org/stable/c/3e3aa6da87d30a0064a17b836685cd43c90a3572"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable code is reached through the KVM_S390_ZPCI_OP VM ioctl, issued by the userspace VMM on behalf of a guest executing the mpcifc \"register adapter interrupts\" instruction for an assigned zPCI device; no network path exists.\nAC:L - The guest simply registers adapter-event notification with no summary bit (sb == 0), which deterministically stores virt_to_phys(page_address(NULL)) into the GAITE; the subsequent wild access is then triggered at will by device interrupt activity or by deregistering/tearing down the VM.\nPR:L - The attacker needs access to a KVM VM file descriptor with an assigned zPCI device, i.e. control of a guest kernel or of the unprivileged QEMU process; no host root or init-namespace privilege is required.\nUI:N - The guest triggers the register/deregister sequence entirely on its own; no host administrator or other user action is needed.\nS:C - A guest action corrupts host kernel state outside the VM's security authority — the GAITE is host-owned and the resulting wild accesses occur in host kernel context, crossing the guest/hypervisor boundary.\nC:H - kvm_s390_pci_aif_disable() turns the bogus physical address into a struct page via phys_to_page() and reads folio metadata from it, an out-of-bounds vmemmap read; the resulting refcount underflow can free memory still in use, yielding a read primitive over host memory belonging to the hypervisor and other guests.\nI:H - aen_host_forward() performs set_bit_inv() on phys_to_virt(garbage) — an atomic OR write at a wild host kernel address — and unpin_user_page() decrements the refcount of a fabricated struct page, giving host memory corruption and a premature-free primitive usable for control-flow hijack.\nA:H - The wild atomic write in hard-IRQ context and the bogus struct page dereference reliably produce an addressing exception / kernel panic in the host, taking down the hypervisor and every guest on it."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:05:54.455Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-68454","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:49:23.202156Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","type":"CWE","description":"CWE-20 Improper Input Validation"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T21:09:11.404Z"}}]}}}