{"api_version":"1","generated_at":"2026-07-24T19:58:57+00:00","cve":"CVE-2024-26906","urls":{"html":"https://cve.report/CVE-2024-26906","api":"https://cve.report/api/cve/CVE-2024-26906.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2024-26906","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-26906"},"summary":{"title":"x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()\n\nWhen trying to use copy_from_kernel_nofault() to read vsyscall page\nthrough a bpf program, the following oops was reported:\n\n  BUG: unable to handle page fault for address: ffffffffff600000\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0\n  Oops: 0000 [#1] PREEMPT SMP PTI\n  CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......\n  RIP: 0010:copy_from_kernel_nofault+0x6f/0x110\n  ......\n  Call Trace:\n   <TASK>\n   ? copy_from_kernel_nofault+0x6f/0x110\n   bpf_probe_read_kernel+0x1d/0x50\n   bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d\n   trace_call_bpf+0xc5/0x1c0\n   perf_call_bpf_enter.isra.0+0x69/0xb0\n   perf_syscall_enter+0x13e/0x200\n   syscall_trace_enter+0x188/0x1c0\n   do_syscall_64+0xb5/0xe0\n   entry_SYSCALL_64_after_hwframe+0x6e/0x76\n   </TASK>\n  ......\n  ---[ end trace 0000000000000000 ]---\n\nThe oops is triggered when:\n\n1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall\npage and invokes copy_from_kernel_nofault() which in turn calls\n__get_user_asm().\n\n2) Because the vsyscall page address is not readable from kernel space,\na page fault exception is triggered accordingly.\n\n3) handle_page_fault() considers the vsyscall page address as a user\nspace address instead of a kernel space address. This results in the\nfix-up setup by bpf not being applied and a page_fault_oops() is invoked\ndue to SMAP.\n\nConsidering handle_page_fault() has already considered the vsyscall page\naddress as a userspace address, fix the problem by disallowing vsyscall\npage read for copy_from_kernel_nofault().","state":"PUBLISHED","assigner":"Linux","published_at":"2024-04-17 11:15:11","updated_at":"2026-05-12 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the Linux kernel, the following vulnerability has been resolved:\n\nx86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()\n\nWhen trying to use copy_from_kernel_nofault() to read vsyscall page\nthrough a bpf program, the following oops was reported:\n\n  BUG: unable to handle page fault for address: ffffffffff600000\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0\n  Oops: 0000 [#1] PREEMPT SMP PTI\n  CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......\n  RIP: 0010:copy_from_kernel_nofault+0x6f/0x110\n  ......\n  Call Trace:\n   <TASK>\n   ? copy_from_kernel_nofault+0x6f/0x110\n   bpf_probe_read_kernel+0x1d/0x50\n   bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d\n   trace_call_bpf+0xc5/0x1c0\n   perf_call_bpf_enter.isra.0+0x69/0xb0\n   perf_syscall_enter+0x13e/0x200\n   syscall_trace_enter+0x188/0x1c0\n   do_syscall_64+0xb5/0xe0\n   entry_SYSCALL_64_after_hwframe+0x6e/0x76\n   </TASK>\n  ......\n  ---[ end trace 0000000000000000 ]---\n\nThe oops is triggered when:\n\n1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall\npage and invokes copy_from_kernel_nofault() which in turn calls\n__get_user_asm().\n\n2) Because the vsyscall page address is not readable from kernel space,\na page fault exception is triggered accordingly.\n\n3) handle_page_fault() considers the vsyscall page address as a user\nspace address instead of a kernel space address. This results in the\nfix-up setup by bpf not being applied and a page_fault_oops() is invoked\ndue to SMAP.\n\nConsidering handle_page_fault() has already considered the vsyscall page\naddress as a userspace address, fix the problem by disallowing vsyscall\npage read for copy_from_kernel_nofault()."}],"providerMetadata":{"dateUpdated":"2026-05-11T20:06:40.672Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6e4694e65b6db4c3de125115dd4f55848cc48381"},{"url":"https://git.kernel.org/stable/c/e8a67fe34b76a49320b33032228a794f40b0316b"},{"url":"https://git.kernel.org/stable/c/f175de546a3eb77614d94d4c02550181c0a8493e"},{"url":"https://git.kernel.org/stable/c/57f78c46f08198e1be08ffe99c4c1ccc12855bf5"},{"url":"https://git.kernel.org/stable/c/29bd6f86904682adafe9affbc7f79b14defcaff8"},{"url":"https://git.kernel.org/stable/c/32019c659ecfe1d92e3bf9fcdfbb11a7c70acd58"}],"title":"x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2024-26906","datePublished":"2024-04-17T10:27:53.573Z","dateReserved":"2024-02-19T14:20:24.187Z","dateUpdated":"2026-05-12T11:50:31.220Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2024-04-17 11:15:11","lastModifiedDate":"2026-05-12 12:16:25","problem_types":["NVD-CWE-noinfo"],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.214","matchCriteriaId":"5CF6C589-38AC-4C84-BCF3-C55CB73D3EB7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.15.153","matchCriteriaId":"ACB69438-845D-4E3C-B114-3140611F9C0B"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.83","matchCriteriaId":"121A07F6-F505-4C47-86BF-9BB6CC7B6C19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.23","matchCriteriaId":"E00814DC-0BA7-431A-9926-80FEB4A96C68"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.7.11","matchCriteriaId":"9B95D3A6-E162-47D5-ABFC-F3FA74FA7CFD"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:*","matchCriteriaId":"B9F4EA73-0894-400F-A490-3A397AB7A517"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:*","matchCriteriaId":"056BD938-0A27-4569-B391-30578B309EE3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:*","matchCriteriaId":"F02056A5-B362-4370-9FF8-6F0BD384D520"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:*","matchCriteriaId":"62075ACE-B2A0-4B16-829D-B3DA5AE5CC41"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:*","matchCriteriaId":"A780F817-2A77-4130-A9B7-5C25606314E3"}]}]},{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*","matchCriteriaId":"07B237A9-69A3-4A9C-9DA0-4E06BD37AE73"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2024","CveId":"26906","Ordinal":"1","Title":"x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault","CVE":"CVE-2024-26906","Year":"2024"},"notes":[{"CveYear":"2024","CveId":"26906","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()\n\nWhen trying to use copy_from_kernel_nofault() to read vsyscall page\nthrough a bpf program, the following oops was reported:\n\n  BUG: unable to handle page fault for address: ffffffffff600000\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0\n  Oops: 0000 [#1] PREEMPT SMP PTI\n  CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......\n  RIP: 0010:copy_from_kernel_nofault+0x6f/0x110\n  ......\n  Call Trace:\n   <TASK>\n   ? copy_from_kernel_nofault+0x6f/0x110\n   bpf_probe_read_kernel+0x1d/0x50\n   bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d\n   trace_call_bpf+0xc5/0x1c0\n   perf_call_bpf_enter.isra.0+0x69/0xb0\n   perf_syscall_enter+0x13e/0x200\n   syscall_trace_enter+0x188/0x1c0\n   do_syscall_64+0xb5/0xe0\n   entry_SYSCALL_64_after_hwframe+0x6e/0x76\n   </TASK>\n  ......\n  ---[ end trace 0000000000000000 ]---\n\nThe oops is triggered when:\n\n1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall\npage and invokes copy_from_kernel_nofault() which in turn calls\n__get_user_asm().\n\n2) Because the vsyscall page address is not readable from kernel space,\na page fault exception is triggered accordingly.\n\n3) handle_page_fault() considers the vsyscall page address as a user\nspace address instead of a kernel space address. This results in the\nfix-up setup by bpf not being applied and a page_fault_oops() is invoked\ndue to SMAP.\n\nConsidering handle_page_fault() has already considered the vsyscall page\naddress as a userspace address, fix the problem by disallowing vsyscall\npage read for copy_from_kernel_nofault().","Type":"Description","Title":"x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault"}]}}}