{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-43840","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-08-17T09:11:59.274Z","datePublished":"2024-08-17T09:21:55.841Z","dateUpdated":"2026-08-05T11:36:42.708Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:36:42.708Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG\n\nWhen BPF_TRAMP_F_CALL_ORIG is set, the trampoline calls\n__bpf_tramp_enter() and __bpf_tramp_exit() functions, passing them\nthe struct bpf_tramp_image *im pointer as an argument in R0.\n\nThe trampoline generation code uses emit_addr_mov_i64() to emit\ninstructions for moving the bpf_tramp_image address into R0, but\nemit_addr_mov_i64() assumes the address to be in the vmalloc() space\nand uses only 48 bits. Because bpf_tramp_image is allocated using\nkzalloc(), its address can use more than 48-bits, in this case the\ntrampoline will pass an invalid address to __bpf_tramp_enter/exit()\ncausing a kernel crash.\n\nFix this by using emit_a64_mov_i64() in place of emit_addr_mov_i64()\nas it can work with addresses that are greater than 48-bits."}],"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 trampoline is generated through the local `bpf()` syscall (BPF_PROG_LOAD + link attach of an fexit/fmod_ret tracing program); there is no network-reachable path to the arm64 JIT.\nAC:L - On an affected system the miscompilation is deterministic — `emit_addr_mov_i64()` unconditionally clobbers bits 48-63 of the kzalloc'd `bpf_tramp_image` address, so every fexit/fmod_ret attach produces a broken trampoline that the attacker triggers simply by invoking the traced function. No race, timing window, or memory layout outside the attacker's influence is involved.\nPR:L - Loading and attaching a BPF_PROG_TYPE_TRACING program requires CAP_BPF plus CAP_PERFMON, which is a delegated non-root capability set commonly granted to unprivileged observability/container workloads and to userns-confined tasks via BPF tokens, not full administrative root.\nUI:N - The attacker loads the program, attaches it, and calls the traced kernel function entirely on its own; no victim action is needed.\nS:U - The wild pointer dereference and any resulting corruption occur within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - `percpu_ref_get()` reads `ref->percpu_count_ptr` from a forged kernel address outside the intended object and treats the result as a live per-CPU pointer, and the broken image refcount can leave freed executable trampoline memory in use — memory corruption of this class is leverageable for kernel memory disclosure.\nI:H - After the wild read, `this_cpu_add(*percpu_count, 1)` (or `atomic_long_add(&ref->data->count)`) performs a read-modify-write through the garbage value, an uncontrolled kernel memory write; additionally the trampoline's liveness refcount is taken on the wrong object, permitting use-after-free of the JIT'd executable image.\nA:H - The forged address lands far outside mapped linear memory, so the first invocation of the traced function takes an unhandled kernel paging fault (oops/panic, possibly in atomic or softirq context), and the poisoned trampoline remains installed so every later call to that function faults again."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/net/bpf_jit_comp.c"],"versions":[{"version":"efc9909fdce00a827a37609628223cd45bf95d0b","lessThan":"077149478497b2f00ff4fd9da2c892defa6418d8","status":"affected","versionType":"git"},{"version":"efc9909fdce00a827a37609628223cd45bf95d0b","lessThan":"d9664e6ff040798a46cdc5d401064f55b8676c83","status":"affected","versionType":"git"},{"version":"efc9909fdce00a827a37609628223cd45bf95d0b","lessThan":"6d218fcc707d6b2c3616b6cd24b948fd4825cfec","status":"affected","versionType":"git"},{"version":"efc9909fdce00a827a37609628223cd45bf95d0b","lessThan":"19d3c179a37730caf600a97fed3794feac2b197b","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/net/bpf_jit_comp.c"],"versions":[{"version":"6.0","status":"affected"},{"version":"0","lessThan":"6.0","status":"unaffected","versionType":"semver"},{"version":"6.1.140","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.92","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.10.3","lessThanOrEqual":"6.10.*","status":"unaffected","versionType":"semver"},{"version":"6.11","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":"6.1.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.6.92"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.10.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.11"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/077149478497b2f00ff4fd9da2c892defa6418d8"},{"url":"https://git.kernel.org/stable/c/d9664e6ff040798a46cdc5d401064f55b8676c83"},{"url":"https://git.kernel.org/stable/c/6d218fcc707d6b2c3616b6cd24b948fd4825cfec"},{"url":"https://git.kernel.org/stable/c/19d3c179a37730caf600a97fed3794feac2b197b"}],"title":"bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2024-43840","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T16:07:58.806748Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-09-12T17:33:04.569Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T19:30:44.552Z"}}]}}