{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99099","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:25:14.391Z","datePublished":"2026-10-26T14:52:04.997Z","dateUpdated":"2026-10-31T12:42:48.094Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-10-31T12:42:48.094Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/CPU/AMD: Fix AMD TLBI Erratum #1718\n\nThe processor may fail to invalidate a TLB entry while executing an\nINVLPGB/TLBSYNC instruction pair.\n\nDetect the erratum and apply a software workaround when a microcode fix\nis not present."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - SYSCALL_DEFINE2(munmap)→__vm_munmap→do_vmi_munmap→do_vmi_align_munmap→vms_complete_munmap_vmas→vms_clear_ptes→unmap_region, which runs unmap_vmas then tlb_finish_mmu→tlb_flush_mmu→tlb_flush→flush_tlb_mm_range→broadcast_tlb_flush→patched __tlbsync; no wire protocol carries the trigger.\nAC:L - An attacker can keep one mm active on four CPUs and repeat munmap until consider_global_asid() assigns a broadcast ASID, prime the target TLB entry, and repeatedly exercise the faulty pair while grooming reuse. CONFIG_BROADCAST_TLB_FLUSH is default on AMD64, and all timing/setup is controlled by the attacker's threads.\nPR:L - SYSCALL_DEFINE2(munmap) reaches the path for ordinary anonymous mappings; do_vmi_munmap() only validates the range, and __vm_munmap() only locks current->mm. No capability, authentication, device permission, or privileged namespace operation is required.\nUI:N - The attacker's own threads create and touch a mapping, call munmap(), and access the stale virtual address after reuse. No victim must mount media, open a file, or perform another action.\nS:U - The failed __tlbsync() leaves a stale host CPU translation and compromises pages managed by the same host kernel. This is ordinary local kernel compromise, not a guest-to-host escape or an IOMMU-boundary bypass.\nC:H - zap_present_folio_ptes() clears the PTE and queues its folio, but tlb_finish_mmu() trusts the faulty __tlbsync() before tlb_batch_pages_flush() recycles it through free_pages_and_swap_cache(). The cached user translation can then read the recycled page, including kernel or other-process data.\nI:H - The same stale writable translation bypasses the cleared page table after free_pages_and_swap_cache() recycles the folio. Grooming that page into kernel objects or page tables provides a kernel-memory write primitive capable of control-flow hijacking.\nA:H - Writes through the stale translation can corrupt a recycled page table or kernel object and cause an oops, panic, or hang. The earlier tlbi=ipi mitigation commit also identifies this INVLPGB/TLBSYNC defect as a cause of observed userspace crashes."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/include/asm/cpufeatures.h","arch/x86/include/asm/tlb.h","arch/x86/kernel/cpu/amd.c"],"versions":[{"version":"82378c6c2f435dba66145609de16bf44a9de6303","lessThan":"e3e6779f77ab6f0a1aa80e24868d2d89f31053fe","status":"affected","versionType":"git"},{"version":"82378c6c2f435dba66145609de16bf44a9de6303","lessThan":"098d80b04d0fe02889c332d061db968f070b83a6","status":"affected","versionType":"git"},{"version":"82378c6c2f435dba66145609de16bf44a9de6303","lessThan":"87db7795cbaaf636ae22ae031f4906db7bb77803","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/include/asm/cpufeatures.h","arch/x86/include/asm/tlb.h","arch/x86/kernel/cpu/amd.c"],"versions":[{"version":"6.15","status":"affected"},{"version":"0","lessThan":"6.15","status":"unaffected","versionType":"semver"},{"version":"6.18.57","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.11","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.2.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.3"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/e3e6779f77ab6f0a1aa80e24868d2d89f31053fe"},{"url":"https://git.kernel.org/stable/c/098d80b04d0fe02889c332d061db968f070b83a6"},{"url":"https://git.kernel.org/stable/c/87db7795cbaaf636ae22ae031f4906db7bb77803"}],"title":"x86/CPU/AMD: Fix AMD TLBI Erratum #1718","x_generator":{"engine":"bippy-1.2.0"}}}}