{"schema":"threatline.record/2","record":{"id":"CVE-2026-98132","aliases":[],"summary":"bpf: don't downgrade half-dead scalar zero spills to STACK_ZERO","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: don't downgrade half-dead scalar zero spills to STACK_ZERO\n\nstates.c:__clean_func_state() can downgrade scalar zero spill to\nSTACK_ZERO in the following case:\n\n  *(u64 *)(r10 - 8) = 0;\n  ... checkpoint ...\n  r1 = *(u32 *)(r10 - 4);\n  ... no reads from r10-8 ...\n\nHere 4 bytes at r10-8 are dead and verifier changes scalar spill to a\ncombination: 0000pppp (p stands for poison). Such a change breaks\nprecision propagation chains. All places that produce STACK_ZERO\nshould call bpf_mark_chain_precision() for the zero source.\n\nThis patch fixes the bug in a simplest way possible:\navoids converting stack spills of zero to STACK_ZERO.\nTwo smarter approaches are possible:\n- do bpf_mark_chain_precision() from __clean_func_state()\n- check slot liveness information in check_stack_write_fixed_off()\n\nI investigated both and the changes required are a bit tricky,\nhence go with a simple fix for the time being.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98132","source_modified_at":"2026-10-19T09:14:26.212Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"be23266b4a08540aa43d8503a2ea10247c8daebe","lessThan":"436fa689630b741a77ef8c4a6f426479affd5bac","status":"affected","versionType":"git"},{"version":"be23266b4a08540aa43d8503a2ea10247c8daebe","lessThan":"2f3536bff8823d3c5fdbbe15e17bfca696cc2b2e","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98132","source_modified_at":"2026-10-19T09:14:26.212Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"7.1","status":"affected"},{"version":"0","lessThan":"7.1","status":"unaffected","versionType":"semver"},{"version":"7.2.7","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98132","source_modified_at":"2026-10-19T09:14:26.212Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"436fa689630b741a77ef8c4a6f426479affd5bac","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98132","source_modified_at":"2026-10-19T09:14:26.212Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"2f3536bff8823d3c5fdbbe15e17bfca696cc2b2e","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00108,"percentile":0.01126,"score_date":"2026-10-23"},"published_at":"2026-09-25T10:36:11.662Z","modified_at":"2026-10-19T09:14:26.212Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98132","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:14:26.212Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98132","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/436fa689630b741a77ef8c4a6f426479affd5bac"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/2f3536bff8823d3c5fdbbe15e17bfca696cc2b2e"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:14:26.212Z","content_hash":"eaf0fea25a29396b4d6d7a76bca039481406b44a7983cb054f296a0f6d081334"}}