{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90358","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.806Z","datePublished":"2026-09-17T16:09:03.531Z","dateUpdated":"2026-09-18T17:54:50.685Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-18T17:54:50.685Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, x86: Fix trampoline stack size for 128-bit arguments\n\nbtf_distill_func_proto() accepts a function argument up to 16 bytes, so a\n128-bit scalar such as __int128 reaches the x86 trampoline with\narg_size == 16. But the current implementation assumes an __int128\nargument only needs one register, so the register save area is\nunder-allocated and save_args() overwrites adjacent stack slots.\n\nCompute the register count from arg_size for all arguments to fix it."}],"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 under-allocation is in __arch_prepare_bpf_trampoline()/save_args() in arch/x86/net/bpf_jit_comp.c and is reached only when a local process issues bpf(BPF_PROG_LOAD) for BPF_PROG_TYPE_TRACING fentry/fexit and bpf(BPF_LINK_CREATE) against a BTF function with a 16-byte integer argument. BPF is a local syscall vector, not a network protocol parser.\nAC:L - The attacker selects an attach target whose BTF has arg_size==16 without BTF_FMODEL_STRUCT_ARG (e.g. bpf_testmod_test_int128_arg). __arch_prepare_bpf_trampoline() then under-counts nr_regs by one slot per such argument and save_args() deterministically overwrites the next stack slot; no race or uninfluenced layout is required.\nPR:L - bpf_prog_load() rejects BPF_PROG_TYPE_TRACING unless bpf_token_capable(CAP_BPF) and, via is_perfmon_prog_type(), bpf_token_capable(CAP_PERFMON). Those capabilities are delegable with BPF tokens and are scored Low, not init-namespace root, consistent with other BPF trampoline CVEs.\nUI:N - The attacker loads the fentry/fexit program, attaches it with BPF_LINK_CREATE, and invokes the target themselves (for bpf_testmod, a read of the module sysfs test file that calls bpf_testmod_test_int128_arg). No separate victim mount or click is required.\nS:U - save_args() overwrites the trampoline's own saved RBP and adjacent slots in the host kernel stack. That is in-kernel memory corruption on the same authority, not a KVM/Xen guest-to-host, IOMMU, or sandbox boundary crossing.\nC:H - The extra 8-byte store of the __int128's second register (RSI) lands in adjacent trampoline slots. On an fentry trampoline without a return-value slot that is saved RBP, so leave pivots RSP through argument contents and subsequent pops/unwinds can disclose kernel stack/memory.\nI:H - The same OOB store overwrites saved RBP (and with two 16-byte scalars, the return address at RBP+8). The trampoline epilogue then executes leave; ret on a corrupted frame, which is kernel stack memory corruption exploitable for a stack pivot and control-flow hijack.\nA:H - Overwriting saved RBP with the high half of a small __int128 (0 for bpf_testmod_test_int128_arg((__int128)1,...)) makes leave load a bogus frame pointer, so the following pop/ret oopses or panics the kernel."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/net/bpf_jit_comp.c"],"versions":[{"version":"a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2","lessThan":"4aed2346fa9b88d458eeb8c01123f3c07585a675","status":"affected","versionType":"git"},{"version":"a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2","lessThan":"40f3bfbbb222b92278f3797614b70f68d46824ac","status":"affected","versionType":"git"},{"version":"a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2","lessThan":"a6d7d7a253c550e74b0651897fe313c2f9b2301f","status":"affected","versionType":"git"},{"version":"a9c5ad31fbdc4dec6d266fe22e51de1ad6d1bcf2","lessThan":"814cba835ef648e0c5eb79505c96c0493b29eea6","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/x86/net/bpf_jit_comp.c"],"versions":[{"version":"6.1","status":"affected"},{"version":"0","lessThan":"6.1","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.52","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"6.1","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/4aed2346fa9b88d458eeb8c01123f3c07585a675"},{"url":"https://git.kernel.org/stable/c/40f3bfbbb222b92278f3797614b70f68d46824ac"},{"url":"https://git.kernel.org/stable/c/a6d7d7a253c550e74b0651897fe313c2f9b2301f"},{"url":"https://git.kernel.org/stable/c/814cba835ef648e0c5eb79505c96c0493b29eea6"}],"title":"bpf, x86: Fix trampoline stack size for 128-bit arguments","x_generator":{"engine":"bippy-1.2.0"}}}}