{"cve":"CVE-2025-38493","nvd":{"published":"2025-07-28T12:15:31.483","modified":"2026-06-17T09:16:58.640","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/osnoise: Fix crash in timerlat_dump_stack()\n\nWe have observed kernel panics when using timerlat with stack saving,\nwith the following dmesg output:\n\nmemcpy: detected buffer overflow: 88 byte write of buffer size 0\nWARNING: CPU: 2 PID: 8153 at lib/string_helpers.c:1032 __fortify_report+0x55/0xa0\nCPU: 2 UID: 0 PID: 8153 Comm: timerlatu/2 Kdump: loaded Not tainted 6.15.3-200.fc42.x86_64 #1 PREEMPT(lazy)\nCall Trace:\n <TASK>\n ? trace_buffer_lock_reserve+0x2a/0x60\n __fortify_panic+0xd/0xf\n __timerlat_dump_stack.cold+0xd/0xd\n timerlat_dump_stack.part.0+0x47/0x80\n timerlat_fd_read+0x36d/0x390\n vfs_read+0xe2/0x390\n ? syscall_exit_to_user_mode+0x1d5/0x210\n ksys_read+0x73/0xe0\n do_syscall_64+0x7b/0x160\n ? exc_page_fault+0x7e/0x1a0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\n__timerlat_dump_stack() constructs the ftrace stack entry like this:\n\nstruct stack_entry *entry;\n...\nmemcpy(&entry->caller, fstack->calls, size);\nentry->size = fstack->nr_entries;\n\nSince commit e7186af7fb26 (\"tracing: Add back FORTIFY_SOURCE logic to\nkernel_stack event structure\"), struct stack_entry marks its caller\nfield with __counted_by(size). At the time of the memcpy, entry->size\ncontains garbage from the ringbuffer, which under some circumstances is\nzero, triggering a kernel panic by buffer overflow.\n\nPopulate the size field before the memcpy so that the out-of-bounds\ncheck knows the correct size. This is analogous to\n__ftrace_trace_stack().","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":["CWE-674"],"references":["https://git.kernel.org/stable/c/7bb9ea515cda027c9e717e27fefcf34f092e7c41","https://git.kernel.org/stable/c/823d798900481875ba6c68217af028c5ffd2976b","https://git.kernel.org/stable/c/85a3bce695b361d85fc528e6fbb33e4c8089c806","https://git.kernel.org/stable/c/fbf90f5aa7ac7cddc69148a71d58f12c8709ce2b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:05:46.678065081+00:00"},"epss":{"cve":"CVE-2025-38493","score":0.00183,"percentile":0.07889,"date":"2026-10-31"},"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."]}