{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-90040 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-90040 is a denial of service vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-90040 and fix it if it is affected.\n\nWhat it is: CVE-2026-90040 is a denial of service vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-90040 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-90040/ (Markdown: https://insights.sbomify.com/CVE-2026-90040/index.md)","id":"CVE-2026-90040","markdown":"https://insights.sbomify.com/CVE-2026-90040/index.md","name":"CVE-2026-90040","record":{"aliases":["BELL-CVE-2026-90040","DEBIAN-CVE-2026-90040","GHSA-hj6j-g456-vf4m","UBUNTU-CVE-2026-90040"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel KVM","requires_auth":"none","summary":"A flaw in Linux KVM SEV-SNP handling allows denial of service when guest memory pages are invalidated without proper VMSA cleanup.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Forcefully invalidate SNP VMSA if its backing gmem page is zapped\n\nWire up a gmem_invalidate_range() call for SNP VMs, and use it to force\nvCPUs to reload/recheck their guest-provided VMSA if the backing gmem\npage is being invalidated, e.g. is being PUNCH_HOLE'd.  Use the same core\nlogic to handle invalidations as VMX does for the APIC-access page, as the\ntwo concepts are nearly identical: shove the physical address of a page\ninto the vCPU's control structure:\n\n 1. Snapshot the invalidation sequence counter\n 2. Grab the pfn (from guest_memfd in this case)\n 3. Acquire mmu_lock for read\n 4. Re-request reload if retry is needed, otherwise commit the change.\n\nNote, the re-request action in #4 is necessary as KVM's retry logic is\nfuzzy, i.e. can get false positives.  If the guest_memfd page has been\ndropped, at some point a subsequent reload will fail to get a PFN from\nguest_memfd, and KVM will fail KVM_RUN.  If the retry was due to a false\npositive, KVM will retry until there are no relevant MMU notifier events\n(and will retry in the \"outer\" loop, i.e. will drop locks and resched as\nneeded).\n\nNote #2!  Take care to invalidate the VMSA when a relevant memslot is\nDELETED or MOVED, as invalidations in response to PUNCH_HOLE are predicated\non memslot bindings (KVM doesn't know what GFN range(s) to invalidate\nwithout a binding).  And more importantly, the VMSA mapping requires a\nmemslot, i.e. must be invalidated if its memslots disappears, regardless of\nthe state of the underlying guest_memfd inode.\n\nFailure to invalidate the vCPU's control.vmsa_pa (which is checked by\npre_sev_run()) can prevent KVM from properly freeing the page as firmware\nwill reject the RMPUPDATE to reclaim the page with FAIL_INUSE if the vCPU\nis actively running, i.e. if VMSA page is in-use.  That in turn leads to an\nRMP #PF on the next use, as the page will still be assigned to the SNP VM.\n\n  SEV-SNP: RMPUPDATE failed for PFN 78d198, pg_level: 1, ret: 3\n  SEV-SNP: PFN 0x78d198, RMP entry: [0xfff0000000144001 - 0x000000000000000f]\n  CPU: 3 UID: 0 PID: 31345 Comm: sev_snp_vmsa_pu Tainted: G     U     O\n  Tainted: [U]=USER, [O]=OOT_MODULE\n  Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.86.0-102 01/25/2026\n  Call Trace:\n   \u003cTASK\u003e\n   dump_stack_lvl+0x54/0x70\n   rmpupdate+0x12c/0x140\n   rmp_make_shared+0x3b/0x60\n   sev_gmem_invalidate+0xe0/0x170 [kvm_amd]\n   delete_from_page_cache_batch+0x1d8/0x220\n   truncate_inode_pages_range+0x120/0x3d0\n   kvm_gmem_fallocate+0x19a/0x270 [kvm]\n   vfs_fallocate+0x1bc/0x1f0\n   __x64_sys_fallocate+0x48/0x70\n   do_syscall_64+0x10a/0x480\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n  RIP: 0033:0x496c7e\n   \u003c/TASK\u003e\n  ------------[ cut here ]------------\n  SEV: Failed to update RMP entry for PFN 0x78d198 error -14\n  WARNING: arch/x86/kvm/svm/sev.c:5160 at sev_gmem_invalidate+0x126/0x170 [kvm_amd], CPU#3: sev_snp_vmsa_pu/31345\n  CPU: 3 UID: 0 PID: 31345 Comm: sev_snp_vmsa_pu Tainted: G     U     O\n  Tainted: [U]=USER, [O]=OOT_MODULE\n  Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.86.0-102 01/25/2026\n  RIP: 0010:sev_gmem_invalidate+0x12b/0x170 [kvm_amd]\n  Call Trace:\n   \u003cTASK\u003e\n   delete_from_page_cache_batch+0x1d8/0x220\n   truncate_inode_pages_range+0x120/0x3d0\n   kvm_gmem_fallocate+0x19a/0x270 [kvm]\n   vfs_fallocate+0x1bc/0x1f0\n   __x64_sys_fallocate+0x48/0x70\n   do_syscall_64+0x10a/0x480\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n  RIP: 0033:0x496c7e\n   \u003c/TASK\u003e\n  irq event stamp: 20689\n  hardirqs last  enabled at (20699): [\u003cffffffff8e76092c\u003e] __console_unlock+0x5c/0x60\n  hardirqs last disabled at (20708): [\u003cffffffff8e760911\u003e] __console_unlock+0x41/0x60\n  softirqs last  enabled at (20722): [\u003cffffffff8e6cd74e\u003e] __irq_exit_rcu+0x7e/0x140\n  softirqs last disabled at (20717): [\u003cffffffff8e6cd74e\u003e] __irq_exit_rcu+0x7e/0x140\n  ---[ end trace 0000000000000000 ]---\n  BUG: unable to handle page fault for address: ffff99\n---truncated---","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"KVM: SEV: Forcefully invalidate SNP VMSA if its backing gmem page is zapped","id":"CVE-2026-90040","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"HID: sony: clean up device list on probe failure","id":"CVE-2026-90041"},"packages":[],"prev":{"headline":"NFSD: Guard admin state-revocation walks with NFSD_NET_UP","id":"CVE-2026-90039"},"products":["Linux"],"published":"2026-09-16","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A flaw in Linux KVM SEV-SNP handling allows denial of service when guest memory pages are invalidated without proper VMSA cleanup.","url":"https://insights.sbomify.com/CVE-2026-90040/"}