{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-74516 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-74516 is a high-severity vulnerability in Linux, published on 15 Aug 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-2026-74516 and fix it if it is affected.\n\nWhat it is: CVE-2026-74516 is a high-severity vulnerability in Linux, published on 15 Aug 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-2026-74516 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-2026-74516/ (Markdown: https://insights.sbomify.com/CVE-2026-74516/index.md)","id":"CVE-2026-74516","markdown":"https://insights.sbomify.com/CVE-2026-74516/index.md","name":"CVE-2026-74516","record":{"aliases":["AZL-96150","BELL-CVE-2026-74516","DEBIAN-CVE-2026-74516","GHSA-p473-wqx8-95rq","UBUNTU-CVE-2026-74516"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel KVM","requires_auth":"high_privilege","summary":"A guest VM can escalate privileges and cause host denial of service by reading APIC state and sending interrupts when AVIC is inhibited during nested virtualization.","user_interaction":"not_required","vuln_class":"privilege_escalation"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":8.2,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active\n\nAlways update x2APIC MSR intercepts for L1 when AVIC is deactivated, even\nif L2 is active and KVM is using a separate MSR bitmap to run L2.  If AVIC\nis fully enabled prior to running L2, and is then inhibited while L2 is\nactive (for a VM-scoped inhibit), then KVM will run L1 with AVIC disabled,\nbut with x2APIC MSR intercepts disabled, i.e. will allow L1 to read most of\nthe host's APIC state, send arbitrary interrupts, change task priority, and\nultimately trivially DoS the host.\n\nE.g. sending a self-IPI in L1 on HYPERV_REENLIGHTENMENT_VECTOR, 0xee, with\nCONFIG_HYPERV=n in the host kernel as a \"safe\" PoC, yields:\n\n  Spurious interrupt (vector 0xee) on CPU#425. Acked\n\nAnd hacking KVM to abuse kvm_set_posted_intr_wakeup_handler() to register a\nhandler and WARN on POSTED_INTR_WAKEUP_VECTOR yields:\n\n  ------------[ cut here ]------------\n  WARNING: arch/x86/kvm/svm/svm.c:5594 at pi_wakeup_handler+0x9/0x10 [kvm_amd], CPU#156: nested_x2apic_t/316940\n  CPU: 156 UID: 0 PID: 316940 Comm: nested_x2apic_t Tainted: G S   U\n  Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER\n  Hardware name: Google Astoria-Turin/astoria, BIOS 0.20260209.0-0 02/09/2026\n  RIP: 0010:pi_wakeup_handler+0x9/0x10 [kvm_amd]\n  Call Trace:\n   \u003cIRQ\u003e\n   sysvec_kvm_posted_intr_wakeup_ipi+0x64/0x80\n   \u003c/IRQ\u003e\n   \u003cTASK\u003e\n   asm_sysvec_kvm_posted_intr_wakeup_ipi+0x1a/0x20\n  RIP: 0010:vcpu_run+0x1430/0x1e40 [kvm]\n   kvm_arch_vcpu_ioctl_run+0x2c1/0x600 [kvm]\n   kvm_vcpu_ioctl+0x580/0x6b0 [kvm]\n   __se_sys_ioctl+0x6d/0xb0\n   do_syscall_64+0x10a/0x480\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n  RIP: 0033:0x46ff4b\n   \u003c/TASK\u003e\n  ---[ end trace 0000000000000000 ]---","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: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active","id":"CVE-2026-74516","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"privilege_escalation","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"KVM: x86: Cancel delayed I/O APIC EOI handling before destroying vCPUs","id":"CVE-2026-74517"},"packages":[],"prev":{"headline":"KVM: s390: pci: Reject adapter interrupt forwarding if already enabled","id":"CVE-2026-74515"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-16","vendors":["Linux"]},"summary":"A guest VM can escalate privileges and cause host denial of service by reading APIC state and sending interrupts when AVIC is inhibited during nested virtualization.","url":"https://insights.sbomify.com/CVE-2026-74516/"}