CVE-2026-23005

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23005", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:45.939Z", "datePublished": "2026-01-25T14:36:19.021Z", "dateUpdated": "2026-11-10T12:41:15.976Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T21:58:09.790Z"}, "descriptions": [{"lang": "en", "value": "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 <TASK>\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 </TASK>\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 <TASK>\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 </TASK>\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---"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kernel/fpu/core.c", "arch/x86/kvm/x86.c"], "versions": [{"version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "b5995c01ba53d84182ecb9492fc4d91cfe8a362d", "status": "affected", "versionType": "git"}, {"version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "1e2848bda819af569dfe7ab186223855e092a2cb", "status": "affected", "versionType": "git"}, {"version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "f577508cc8a0adb8b4ebe9480bba7683b6149930", "status": "affected", "versionType": "git"}, {"version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "eea6f395ca502c4528314c8112da9b5d65f685eb", "status": "affected", "versionType": "git"}, {"version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "b45f721775947a84996deb5c661602254ce25ce6", "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/kernel/fpu/core.c", "arch/x86/kvm/x86.c"], "versions": [{"version": "5.17", "status": "affected"}, {"version": "0", "lessThan": "5.17", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.162", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.122", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.67", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.7", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19", "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": "5.17", "versionEndExcluding": "6.1.162"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.6.122"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.12.67"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.18.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.19"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/b5995c01ba53d84182ecb9492fc4d91cfe8a362d"}, {"url": "https://git.kernel.org/stable/c/1e2848bda819af569dfe7ab186223855e092a2cb"}, {"url": "https://git.kernel.org/stable/c/f577508cc8a0adb8b4ebe9480bba7683b6149930"}, {"url": "https://git.kernel.org/stable/c/eea6f395ca502c4528314c8112da9b5d65f685eb"}, {"url": "https://git.kernel.org/stable/c/b45f721775947a84996deb5c661602254ce25ce6"}], "title": "x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-23005", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-10T20:42:31.188844Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-20", "description": "CWE-20 Improper Input Validation"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T18:25:27.665Z"}}, {"x_adpType": "supplier", "providerMetadata": {"orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-11-10T12:41:15.976Z"}, "affected": [{"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], 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"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", 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"134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-06-11T17:39:29.813Z"}}], "cna": {"title": "x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1", "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "b5995c01ba53d84182ecb9492fc4d91cfe8a362d", "versionType": "git"}, {"status": "affected", "version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "1e2848bda819af569dfe7ab186223855e092a2cb", "versionType": "git"}, {"status": "affected", "version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "f577508cc8a0adb8b4ebe9480bba7683b6149930", "versionType": "git"}, {"status": "affected", "version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "eea6f395ca502c4528314c8112da9b5d65f685eb", "versionType": "git"}, {"status": "affected", "version": "820a6ee944e74e57255ac2e90916ecdaade57b95", "lessThan": "b45f721775947a84996deb5c661602254ce25ce6", "versionType": "git"}], "programFiles": ["arch/x86/kernel/fpu/core.c", "arch/x86/kvm/x86.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.17"}, {"status": "unaffected", "version": "0", "lessThan": "5.17", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.162", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.122", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.67", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.7", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["arch/x86/kernel/fpu/core.c", "arch/x86/kvm/x86.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/b5995c01ba53d84182ecb9492fc4d91cfe8a362d"}, {"url": "https://git.kernel.org/stable/c/1e2848bda819af569dfe7ab186223855e092a2cb"}, {"url": "https://git.kernel.org/stable/c/f577508cc8a0adb8b4ebe9480bba7683b6149930"}, {"url": "https://git.kernel.org/stable/c/eea6f395ca502c4528314c8112da9b5d65f685eb"}, {"url": "https://git.kernel.org/stable/c/b45f721775947a84996deb5c661602254ce25ce6"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "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 <TASK>\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 </TASK>\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 <TASK>\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 </TASK>\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---"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.162", "versionStartIncluding": "5.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.122", "versionStartIncluding": "5.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.67", "versionStartIncluding": "5.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.7", "versionStartIncluding": "5.17"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.19", "versionStartIncluding": "5.17"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T21:58:09.790Z"}}}, "cveMetadata": {"cveId": "CVE-2026-23005", "state": "PUBLISHED", "dateUpdated": "2026-11-10T12:41:15.976Z", "dateReserved": "2026-01-13T15:37:45.939Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-01-25T14:36:19.021Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

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(6ES7518-4FX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}], "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "DBDA7572-E110-41C4-9105-D1C8795D891A", "versionEndExcluding": "6.1.162", "versionStartIncluding": "5.17.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8EAAE395-0162-4BAF-9AD5-E9AF3C869C4F", "versionEndExcluding": "6.6.122", "versionStartIncluding": "6.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7456F614-6AA8-4C08-8229-BA342D4AFBAD", "versionEndExcluding": "6.12.67", "versionStartIncluding": "6.7", "vulnerable": true}, 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"matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*", "matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*", "matchCriteriaId": "F5DC0CA6-F0AF-4DDF-A882-3DADB9A886A7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*", "matchCriteriaId": "EB5B7DFC-C36B-45D8-922C-877569FDDF43", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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 <TASK>\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 </TASK>\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 <TASK>\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 </TASK>\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---"}], "id": "CVE-2026-23005", "lastModified": "2026-11-10T13:18:32.570", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-23005", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-06-10T20:42:31.188844Z", "version": "2.0.3"}}]}, "published": "2026-01-25T15:15:55.377", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1e2848bda819af569dfe7ab186223855e092a2cb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b45f721775947a84996deb5c661602254ce25ce6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b5995c01ba53d84182ecb9492fc4d91cfe8a362d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/eea6f395ca502c4528314c8112da9b5d65f685eb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f577508cc8a0adb8b4ebe9480bba7683b6149930"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-20"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1", "id": "2432658", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2432658"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-23005", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-01-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23005\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23005\nhttps://lore.kernel.org/linux-cve-announce/2026012536-CVE-2026-23005-df15@gregkh/T"], "threat_severity": "Low"}

{"created": "2026-04-18T15:15:03.689260+00:00", "updated": "2026-10-23T09:00:15.797194+00:00", "vendors": []}