{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-54303", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-30T12:06:44.529Z", "datePublished": "2025-12-30T12:23:37.827Z", "dateUpdated": "2026-08-05T09:19:03.573Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:19:03.573Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Disable preemption in bpf_perf_event_output\n\nThe nesting protection in bpf_perf_event_output relies on disabled\npreemption, which is guaranteed for kprobes and tracepoints.\n\nHowever bpf_perf_event_output can be also called from uprobes context\nthrough bpf_prog_run_array_sleepable function which disables migration,\nbut keeps preemption enabled.\n\nThis can cause task to be preempted by another one inside the nesting\nprotection and lead eventually to two tasks using same perf_sample_data\nbuffer and cause crashes like:\n\n kernel tried to execute NX-protected page - exploit attempt? (uid: 0)\n BUG: unable to handle page fault for address: ffffffff82be3eea\n ...\n Call Trace:\n ? __die+0x1f/0x70\n ? page_fault_oops+0x176/0x4d0\n ? exc_page_fault+0x132/0x230\n ? asm_exc_page_fault+0x22/0x30\n ? perf_output_sample+0x12b/0x910\n ? perf_event_output+0xd0/0x1d0\n ? bpf_perf_event_output+0x162/0x1d0\n ? bpf_prog_c6271286d9a4c938_krava1+0x76/0x87\n ? __uprobe_perf_func+0x12b/0x540\n ? uprobe_dispatcher+0x2c4/0x430\n ? uprobe_notify_resume+0x2da/0xce0\n ? atomic_notifier_call_chain+0x7b/0x110\n ? exit_to_user_mode_prepare+0x13e/0x290\n ? irqentry_exit_to_user_mode+0x5/0x30\n ? asm_exc_int3+0x35/0x40\n\nFixing this by disabling preemption in bpf_perf_event_output." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable code is BPF/uprobe tracing infrastructure reached only by executing code on the machine (hitting an instrumented userspace function via local process execution). There is no remote or adjacent-network entry point.\nAC:L - The attacker controls both racing sides — they run all the threads that hit the uprobe — and can pin them to a single CPU with sched_setaffinity, widen the window with large bpf_perf_event_output payloads, and rely on full preemption being the default on PREEMPT_DYNAMIC distro and Android kernels. Nothing required is outside attacker influence.\nPR:L - In the realistic worst case — a host running a system-wide uprobe/USDT observability agent (bpftrace, BCC, continuous profiler), whose programs use perf_submit()/bpf_perf_event_output by default — any unprivileged local user triggers the corruption merely by executing the instrumented binary concurrently. No capability of the attacker's own is needed.\nUI:N - The attacker's own threads hit the uprobe and generate the preemption; no victim action or interaction is required.\nS:U - The corrupted per-CPU perf_sample_data and the resulting code execution are entirely within the kernel's own security authority, with no crossing into a hypervisor, IOMMU, or other authority.\nC:H - The shared slot leaves data->raw pointing at another task's freed/reused kernel stack, so __output_copy() copies frag->size bytes from an arbitrary frag->data pointer into the mmapped perf ring buffer, yielding arbitrary kernel memory disclosure.\nI:H - __output_custom() performs an indirect call through frag->copy read from a reused kernel stack — confirmed by the \"kernel tried to execute NX-protected page - exploit attempt?\" oops — giving an attacker-sprayable control-flow hijack primitive on top of concurrent writes to a shared perf_sample_data.\nA:H - The commit message documents a reproducible kernel page fault / oops in perf_output_sample, and the race can be re-triggered at will to repeatedly panic the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/trace/bpf_trace.c" ], "versions": [ { "version": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9", "lessThan": "3654ed5daf492463c3faa434c7000d45c2da2ace", "status": "affected", "versionType": "git" }, { "version": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9", "lessThan": "a0ac32cf61e5a76e2429e486925a52ee41dd75e3", "status": "affected", "versionType": "git" }, { "version": "8c7dcb84e3b744b2b70baa7a44a9b1881c33a9c9", "lessThan": "f2c67a3e60d1071b65848efaa8c3b66c363dd025", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/trace/bpf_trace.c" ], "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.45", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.4.10", "lessThanOrEqual": "6.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.5", "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": "6.0", "versionEndExcluding": "6.1.45" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.4.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.5" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3654ed5daf492463c3faa434c7000d45c2da2ace" }, { "url": "https://git.kernel.org/stable/c/a0ac32cf61e5a76e2429e486925a52ee41dd75e3" }, { "url": "https://git.kernel.org/stable/c/f2c67a3e60d1071b65848efaa8c3b66c363dd025" } ], "title": "bpf: Disable preemption in bpf_perf_event_output", "x_generator": { "engine": "bippy-1.2.0" } } } }