{"id":"CVE-2026-43321","state":"PUBLISHED","title":"bpf: Properly mark live registers for indirect jumps","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Properly mark live registers for indirect jumps\n\nFor a `gotox rX` instruction the rX register should be marked as used\nin the compute_insn_live_regs() function. Fix this.","publishedAt":"2026-05-08T13:26:15.600Z","updatedAt":"2026-10-19T19:16:26.326Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"493d9e0d608339a32f568504d5fd411a261bb0af","status":"affected","lessThan":"7beae54111c34ca63357ef120e115889b915beb5","versionType":"git"},{"version":"493d9e0d608339a32f568504d5fd411a261bb0af","status":"affected","lessThan":"d1aab1ca576c90192ba961094d51b0be6355a4d6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/verifier.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.19.6","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/verifier.c"]}],"references":["https://git.kernel.org/stable/c/7beae54111c34ca63357ef120e115889b915beb5","https://git.kernel.org/stable/c/d1aab1ca576c90192ba961094d51b0be6355a4d6"],"weaknesses":["CWE-682"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/43xxx/CVE-2026-43321.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43321","state":"PUBLISHED","datePublished":"2026-05-08T13:26:15.600Z","dateUpdated":"2026-10-19T19:16:26.326Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-01T14:12:56.001Z"},"containers":{"cna":{"title":"bpf: Properly mark live registers for indirect jumps","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Properly mark live registers for indirect jumps\n\nFor a `gotox rX` instruction the rX register should be marked as used\nin the compute_insn_live_regs() function. Fix this."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"493d9e0d608339a32f568504d5fd411a261bb0af","status":"affected","lessThan":"7beae54111c34ca63357ef120e115889b915beb5","versionType":"git"},{"version":"493d9e0d608339a32f568504d5fd411a261bb0af","status":"affected","lessThan":"d1aab1ca576c90192ba961094d51b0be6355a4d6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/verifier.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.19.6","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/verifier.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7beae54111c34ca63357ef120e115889b915beb5"},{"url":"https://git.kernel.org/stable/c/d1aab1ca576c90192ba961094d51b0be6355a4d6"}],"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 verifier path is reached by a local caller through the bpf() syscall with BPF_PROG_LOAD and BPF_MAP_TYPE_INSN_ARRAY setup. It is not reachable directly from network packets or a remote protocol.\nAC:L - An attacker who can load the relevant BPF program can craft bytecode and jump-table contents to reach the faulty liveness/pruning behavior without a race or victim-dependent state. The bug is deterministic verifier logic.\nPR:L - Loading the needed BPF objects is privilege-gated, but CAP_BPF/BPF-token delegated environments and namespace-based BPF delegation make this reachable by a low-privileged local attacker in reasonable deployments. Under the required tie-break rule, this is scored as low rather than high privileges.\nUI:N - No victim action is required after the attacker invokes the local BPF syscalls. The attacker supplies the program and map contents directly.\nS:U - Successful exploitation compromises the kernel in the same security authority as the vulnerable verifier. This is standard local kernel privilege escalation, not a VM or IOMMU boundary escape.\nC:H - The missing live-register mark can make verifier state pruning ignore the indirect-jump target register, potentially admitting unsafe BPF execution paths. Verifier unsoundness of this kind can be leveraged for arbitrary kernel memory disclosure.\nI:H - If an unsafe BPF program is accepted, the attacker can plausibly obtain arbitrary kernel memory write or control-flow primitives. This supports full kernel integrity compromise.\nA:H - Even without full exploitation, an accepted unsafe BPF program can corrupt kernel memory or execute invalid accesses and crash or panic the kernel. Availability impact is therefore high."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:27:12.004Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"6.19.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-43321","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:16:22.780603Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-682","lang":"en","type":"CWE","description":"CWE-682 Incorrect Calculation"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T19:16:26.326Z"}}]}}}