{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72426","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-09T03:40:39.928Z","datePublished":"2026-08-15T05:56:43.575Z","dateUpdated":"2026-08-17T05:44:06.105Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T05:44:06.105Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Preserve pointer spill metadata during half-slot cleanup\n\n__clean_func_state() cleans dead stack slots in 4-byte halves. When the\nhigh half of a STACK_SPILL slot is dead and the low half remains live,\ncleanup converts the live low half to STACK_MISC or STACK_ZERO and clears\nthe saved spilled_ptr metadata.\n\nThat conversion is safe only for scalar spills. For a pointer spill, this\nmetadata clear lets a later 32-bit fill from the still-live half avoid the\nnormal non-scalar register-fill check and be treated as an ordinary scalar\nstack read.\n\nLeave non-scalar spill slots intact in this half-live shape. This is\nconservative for pruning and preserves the existing\ncheck_stack_read_fixed_off() rejection path for partial fills from pointer\nspills."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.4,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The flaw is reached only through the local bpf(BPF_PROG_LOAD) syscall during BPF verifier state pruning in bpf_is_state_visited()->clean_verifier_state()->__clean_func_state(), which is a local kernel interface per BPF CVSS guidance.\nAC:L - An attacker fully controls the crafted BPF bytecode, can spill a pointer, force verifier checkpoints (e.g., BPF_F_TEST_STATE_FREQ or branch pruning), and reliably trigger the half-slot cleanup path without races or external timing.\nPR:N - Exploitation occurs at BPF_PROG_LOAD via bpf(); on systems with kernel.unprivileged_bpf_disabled=0, unprivileged users can load socket-filter programs that trigger this verifier path without CAP_BPF or init-namespace root.\nUI:N - No victim interaction is required; the attacker loads and verifies their own malicious BPF program through the bpf() syscall.\nS:U - Impact is a BPF verifier bypass leading to kernel memory corruption and local privilege escalation within the same kernel security boundary, not a cross-authority escape such as VM guest-to-host.\nC:H - Cleared pointer spill metadata lets partial 32-bit fills bypass non-scalar register-fill checks, causing verifier/runtime type confusion that can be developed into arbitrary kernel memory disclosure primitives.\nI:H - Verifier-approved programs can treat pointer spill bytes as scalars and perform unsafe memory operations, enabling out-of-bounds writes and control-flow hijacking for arbitrary kernel code execution from BPF context.\nA:H - Executing verifier-incorrect BPF with confused pointer/scalar state can trigger kernel oops or panic, and the attacker can repeatedly load and run crafted programs to cause denial of service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/states.c"],"versions":[{"version":"be23266b4a08540aa43d8503a2ea10247c8daebe","lessThan":"0f9278b22cda6fd2525049930157b79b4036b4ef","status":"affected","versionType":"git"},{"version":"be23266b4a08540aa43d8503a2ea10247c8daebe","lessThan":"3a354149bceacadbcf7d7b4766f5ef26a85892ab","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/bpf/states.c"],"versions":[{"version":"7.1","status":"affected"},{"version":"0","lessThan":"7.1","status":"unaffected","versionType":"semver"},{"version":"7.1.5","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","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":"7.1","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/0f9278b22cda6fd2525049930157b79b4036b4ef"},{"url":"https://git.kernel.org/stable/c/3a354149bceacadbcf7d7b4766f5ef26a85892ab"}],"title":"bpf: Preserve pointer spill metadata during half-slot cleanup","x_generator":{"engine":"bippy-1.2.0"}}}}