{"id":"CVE-2026-98033","state":"PUBLISHED","title":"bpf: Preserve inner map identity in callback frames","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Preserve inner map identity in callback frames\n\nCallback frame constructors initialize map-typed argument registers with\n__mark_reg_known_zero() and then restore map_ptr. This clears map_uid,\nwhich is the only field distinguishing inner maps that share an\ninner_map_meta template.\n\nWhen a timer callback invokes bpf_for_each_map_elem() on a second inner\nmap, both the saved first map and the second map value can reach the nested\ncallback as the same template with map_uid zero. bpf_timer_init() then\naccepts pairing the timer from the second map with the first map.\n\nThe runtime records the first map in the timer without taking a reference.\nFreeing that map does not find the timer stored in the second map, so a\nlater timer callback dereferences the freed map.\n\nCopy map_uid from the same caller register as map_ptr when constructing\nfor-each, timer/workqueue, and task-work callback arguments. The existing\nidentity check can then reject mismatched inner maps while allowing a\ncallback value to be paired with its actual map.","publishedAt":"2026-09-25T10:23:48.761Z","updatedAt":"2026-10-21T12:54:07.398Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"cf85e4f94d7feef8b3c4c90dbe2468595a48393b","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"166221c52d3ca332f8699a854efca8e2704bb137","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"08b534bafdd9de65b6374474a8fe719c90eb3b01","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"66ff2eff093d2a0838f39c713eeb590bc0946c2a","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"b90c5d770dad910fb89e6c1b15052a8a1e8db752","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":"5.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.13","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","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/cf85e4f94d7feef8b3c4c90dbe2468595a48393b","https://git.kernel.org/stable/c/166221c52d3ca332f8699a854efca8e2704bb137","https://git.kernel.org/stable/c/08b534bafdd9de65b6374474a8fe719c90eb3b01","https://git.kernel.org/stable/c/66ff2eff093d2a0838f39c713eeb590bc0946c2a","https://git.kernel.org/stable/c/b90c5d770dad910fb89e6c1b15052a8a1e8db752"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98033.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98033","state":"PUBLISHED","datePublished":"2026-09-25T10:23:48.761Z","dateUpdated":"2026-10-21T12:54:07.398Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:19:56.070Z"},"containers":{"cna":{"title":"bpf: Preserve inner map identity in callback frames","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Preserve inner map identity in callback frames\n\nCallback frame constructors initialize map-typed argument registers with\n__mark_reg_known_zero() and then restore map_ptr. This clears map_uid,\nwhich is the only field distinguishing inner maps that share an\ninner_map_meta template.\n\nWhen a timer callback invokes bpf_for_each_map_elem() on a second inner\nmap, both the saved first map and the second map value can reach the nested\ncallback as the same template with map_uid zero. bpf_timer_init() then\naccepts pairing the timer from the second map with the first map.\n\nThe runtime records the first map in the timer without taking a reference.\nFreeing that map does not find the timer stored in the second map, so a\nlater timer callback dereferences the freed map.\n\nCopy map_uid from the same caller register as map_ptr when constructing\nfor-each, timer/workqueue, and task-work callback arguments. The existing\nidentity check can then reject mismatched inner maps while allowing a\ncallback value to be paired with its actual map."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"cf85e4f94d7feef8b3c4c90dbe2468595a48393b","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"166221c52d3ca332f8699a854efca8e2704bb137","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"08b534bafdd9de65b6374474a8fe719c90eb3b01","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"66ff2eff093d2a0838f39c713eeb590bc0946c2a","versionType":"git"},{"version":"69c087ba6225b574afb6e505b72cb75242a3d844","status":"affected","lessThan":"b90c5d770dad910fb89e6c1b15052a8a1e8db752","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":"5.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.13","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","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/cf85e4f94d7feef8b3c4c90dbe2468595a48393b"},{"url":"https://git.kernel.org/stable/c/166221c52d3ca332f8699a854efca8e2704bb137"},{"url":"https://git.kernel.org/stable/c/08b534bafdd9de65b6374474a8fe719c90eb3b01"},{"url":"https://git.kernel.org/stable/c/66ff2eff093d2a0838f39c713eeb590bc0946c2a"},{"url":"https://git.kernel.org/stable/c/b90c5d770dad910fb89e6c1b15052a8a1e8db752"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-21T12:54:07.398Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"6.12.114"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}