{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-23005 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-23005 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jan 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-2026-23005 and fix it if it is affected.\n\nWhat it is: CVE-2026-23005 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Jan 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-2026-23005 in the wild and no public exploit code.\n\nAffected product: Linux kernel. 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-2026-23005/ (Markdown: https://insights.sbomify.com/CVE-2026-23005/index.md)","id":"CVE-2026-23005","markdown":"https://insights.sbomify.com/CVE-2026-23005/index.md","name":"CVE-2026-23005","record":{"aliases":["AZL-77175","BELL-CVE-2026-23005","DEBIAN-CVE-2026-23005","GHSA-326g-5c6q-7782","ROOT-OS-UBUNTU-2404-CVE-2026-23005","UBUNTU-CVE-2026-23005"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel KVM","requires_auth":"low_privilege","summary":"A guest VM can crash the host kernel by triggering a kernel panic via improper XSAVE state handling in KVM.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-20","name":"Improper Input Validation"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1\n\nWhen loading guest XSAVE state via KVM_SET_XSAVE, and when updating XFD in\nresponse to a guest WRMSR, clear XFD-disabled features in the saved (or to\nbe restored) XSTATE_BV to ensure KVM doesn't attempt to load state for\nfeatures that are disabled via the guest's XFD.  Because the kernel\nexecutes XRSTOR with the guest's XFD, saving XSTATE_BV[i]=1 with XFD[i]=1\nwill cause XRSTOR to #NM and panic the kernel.\n\nE.g. if fpu_update_guest_xfd() sets XFD without clearing XSTATE_BV:\n\n  ------------[ cut here ]------------\n  WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#29: amx_test/848\n  Modules linked in: kvm_intel kvm irqbypass\n  CPU: 29 UID: 1000 PID: 848 Comm: amx_test Not tainted 6.19.0-rc2-ffa07f7fd437-x86_amx_nm_xfd_non_init-vm #171 NONE\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:exc_device_not_available+0x101/0x110\n  Call Trace:\n   \u003cTASK\u003e\n   asm_exc_device_not_available+0x1a/0x20\n  RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90\n   switch_fpu_return+0x4a/0xb0\n   kvm_arch_vcpu_ioctl_run+0x1245/0x1e40 [kvm]\n   kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm]\n   __x64_sys_ioctl+0x8f/0xd0\n   do_syscall_64+0x62/0x940\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n   \u003c/TASK\u003e\n  ---[ end trace 0000000000000000 ]---\n\nThis can happen if the guest executes WRMSR(MSR_IA32_XFD) to set XFD[18] = 1,\nand a host IRQ triggers kernel_fpu_begin() prior to the vmexit handler's\ncall to fpu_update_guest_xfd().\n\nand if userspace stuffs XSTATE_BV[i]=1 via KVM_SET_XSAVE:\n\n  ------------[ cut here ]------------\n  WARNING: arch/x86/kernel/traps.c:1524 at exc_device_not_available+0x101/0x110, CPU#14: amx_test/867\n  Modules linked in: kvm_intel kvm irqbypass\n  CPU: 14 UID: 1000 PID: 867 Comm: amx_test Not tainted 6.19.0-rc2-2dace9faccd6-x86_amx_nm_xfd_non_init-vm #168 NONE\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:exc_device_not_available+0x101/0x110\n  Call Trace:\n   \u003cTASK\u003e\n   asm_exc_device_not_available+0x1a/0x20\n  RIP: 0010:restore_fpregs_from_fpstate+0x36/0x90\n   fpu_swap_kvm_fpstate+0x6b/0x120\n   kvm_load_guest_fpu+0x30/0x80 [kvm]\n   kvm_arch_vcpu_ioctl_run+0x85/0x1e40 [kvm]\n   kvm_vcpu_ioctl+0x2c3/0x8f0 [kvm]\n   __x64_sys_ioctl+0x8f/0xd0\n   do_syscall_64+0x62/0x940\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n   \u003c/TASK\u003e\n  ---[ end trace 0000000000000000 ]---\n\nThe new behavior is consistent with the AMX architecture.  Per Intel's SDM,\nXSAVE saves XSTATE_BV as '0' for components that are disabled via XFD\n(and non-compacted XSAVE saves the initial configuration of the state\ncomponent):\n\n  If XSAVE, XSAVEC, XSAVEOPT, or XSAVES is saving the state component i,\n  the instruction does not generate #NM when XCR0[i] = IA32_XFD[i] = 1;\n  instead, it operates as if XINUSE[i] = 0 (and the state component was\n  in its initial state): it saves bit i of XSTATE_BV field of the XSAVE\n  header as 0; in addition, XSAVE saves the initial configuration of the\n  state component (the other instructions do not save state component i).\n\nAlternatively, KVM could always do XRSTOR with XFD=0, e.g. by using\na constant XFD based on the set of enabled features when XSAVEing for\na struct fpu_guest.  However, having XSTATE_BV[i]=1 for XFD-disabled\nfeatures can only happen in the above interrupt case, or in similar\nscenarios involving preemption on preemptible kernels, because\nfpu_swap_kvm_fpstate()'s call to save_fpregs_to_fpstate() saves the\noutgoing FPU state with the current XFD; and that is (on all but the\nfirst WRMSR to XFD) the guest XFD.\n\nTherefore, XFD can only go out of sync with XSTATE_BV in the above\ninterrupt case, or in similar scenarios involving preemption on\npreemptible kernels, and it we can consider it (de facto) part of KVM\nABI that KVM_GET_XSAVE returns XSTATE_BV[i]=0 for XFD-disabled features.\n\n[Move clea\n---truncated---","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":"2026-08-05","github_poc":1,"max_poc_stars":1,"metasploit":0,"nuclei":0,"refs":[{"date":"2026-08-05T21:25:36Z","kind":"github_poc","ref":"https://github.com/George0Papasotiriou/CVE-2026-23005-Matter-Commissioning-Code-Brute-Force-Without-Rate-Limit","stars":1,"title":null}],"tier":"poc_unverified"},"has_fix":true,"headline":"x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1","id":"CVE-2026-23005","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"ASoC: tlv320adcx140: fix null pointer","id":"CVE-2026-23006"},"packages":[],"prev":{"headline":"dst: fix races in rt6_uncached_list_del() and rt_del_uncached_list()","id":"CVE-2026-23004"},"products":["Linux"],"published":"2026-01-25","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A guest VM can crash the host kernel by triggering a kernel panic via improper XSAVE state handling in KVM.","url":"https://insights.sbomify.com/CVE-2026-23005/"}