{"cve":"CVE-2024-26906","nvd":{"published":"2024-04-17T11:15:11.207","modified":"2026-10-15T01:17:31.353","status":"Modified","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().","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/29bd6f86904682adafe9affbc7f79b14defcaff8","https://git.kernel.org/stable/c/32019c659ecfe1d92e3bf9fcdfbb11a7c70acd58","https://git.kernel.org/stable/c/57f78c46f08198e1be08ffe99c4c1ccc12855bf5","https://git.kernel.org/stable/c/6e4694e65b6db4c3de125115dd4f55848cc48381","https://git.kernel.org/stable/c/e8a67fe34b76a49320b33032228a794f40b0316b"],"products":["debian:debian_linux","linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:49:08.435428910+00:00"},"epss":{"cve":"CVE-2024-26906","score":0.00253,"percentile":0.16596,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}