{"id":"CVE-2025-39683","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-39683","generatedAt":"2026-10-28T04:34:03.691Z","title":"In the Linux kernel, the following vulnerability has been resolved: tracing: Limit access to parser->buffer when trace_get_user failed When the length of the string written to set_ftrace_filter exceeds FTRACE_BUFF_MAX, the following KASAN alarm will be…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Limit access to parser->buffer when trace_get_user failed\n\nWhen the length of the string written to set_ftrace_filter exceeds\nFTRACE_BUFF_MAX, the following KASAN alarm will be triggered:\n\nBUG: KASAN: slab-out-of-bounds in strsep+0x18c/0x1b0\nRead of size 1 at addr ffff0000d00bd5ba by task ash/165\n\nCPU: 1 UID: 0 PID: 165 Comm: ash Not tainted 6.16.0-g6bcdbd62bd56-dirty\nHardware name: linux,dummy-virt (DT)\nCall trace:\n show_stack+0x34/0x50 (C)\n dump_stack_lvl+0xa0/0x158\n print_address_description.constprop.0+0x88/0x398\n print_report+0xb0/0x280\n kasan_report+0xa4/0xf0\n __asan_report_load1_noabort+0x20/0x30\n strsep+0x18c/0x1b0\n ftrace_process_regex.isra.0+0x100/0x2d8\n ftrace_regex_release+0x484/0x618\n __fput+0x364/0xa58\n ____fput+0x28/0x40\n task_work_run+0x154/0x278\n do_notify_resume+0x1f0/0x220\n el0_svc+0xec/0xf0\n el0t_64_sync_handler+0xa0/0xe8\n el0t_64_sync+0x1ac/0x1b0\n\nThe reason is that trace_get_user will fail when processing a string\nlonger than FTRACE_BUFF_MAX, but not set the end of parser->buffer to 0.\nThen an OOB access will be triggered in ftrace_regex_release->\nftrace_process_regex->strsep->strpbrk. We can solve this problem by\nlimiting access to parser->buffer when trace_get_user failed.","published":"2025-09-05T18:15:45.000Z","lastModified":"2026-10-19T21:10:00.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":7.1,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"},"cwe":["CWE-125"],"affected":["linux/linux kernel","debian/debian linux"],"epss":{"score":0.00184,"percentile":0.07952,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/3079517a5ba80901fe828a06998da64b9b8749be","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/418b448e1d7470da9d4d4797f71782595ee69c49","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/41b838420457802f21918df66764b6fbf829d330","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/58ff8064cb4c7eddac4da1a59da039ead586950a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6a909ea83f226803ea0e718f6e88613df9234d58","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b842ef39c2ad6156c13afdec25ecc6792a9b67b9","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d0c68045b8b0f3737ed7bd6b8c83b7887014adee","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","source":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-39683","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}