{"api_version":"1","generated_at":"2026-09-18T01:33:55+00:00","cve":"CVE-2026-90246","urls":{"html":"https://cve.report/CVE-2026-90246","api":"https://cve.report/api/cve/CVE-2026-90246.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-90246","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-90246"},"summary":{"title":"apparmor: fix integer overflow in verify_tags() bounds check","description":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix integer overflow in verify_tags() bounds check\n\nverify_tags() validates the tagset table unpacked from a policy blob.\nFor each set it reads a count and checks that advancing the index by\nthat count stays inside sets.table[]:\n\n\tu32 cnt = tags->sets.table[i];\n\n\tif (i+cnt >= tags->sets.size) {\n\ni, cnt and sets.size are all u32, so i+cnt is evaluated modulo 2^32.\nsets.table[] is filled by unpack_tagsets() with aa_unpack_u32(), so\nevery entry is a raw unbounded 32-bit word taken from the policy blob,\nand verify_tags() is the function that is supposed to validate it.  A\ncount close to U32_MAX makes the sum wrap to a small value, the guard\npasses, and the inner loop then walks sets.table[++i] past the end of\nthe kcalloc(size, sizeof(u32)) allocation.\n\nNote that sets.size is bounded by 65535, because unpack_tagsets() reads\nit with aa_unpack_array() as a u16, so the wrap cannot be reached by\ngrowing the table; it is reached purely through the attacker-supplied\ncount.\n\nWith sets.size = 2 and sets.table = { 0, 0xffffffff }:\n\n  i = 0: cnt = 0, guard 0 + 0 >= 2 is false, inner loop does not run\n  i = 1: cnt = 0xffffffff, guard (1 + 0xffffffff) mod 2^32 == 0 >= 2 is\n         false, so the guard is bypassed and the inner loop reads\n         sets.table[2] -- one element past a two element allocation\n\nThe walk continues until an out-of-bounds value happens to be >=\nhdrs.size or the access faults, so a crafted policy yields an\nout-of-bounds read on the policy load path\n(aa_replace_profiles -> aa_unpack -> unpack_policydb -> unpack_tags ->\nverify_tags).  unpack_tags() runs before the perms and DFA tables are\nunpacked, so no other table needs to be well formed to reach it.\n\nPolicy load is gated by aa_may_manage_policy(), which checks\nCAP_MAC_ADMIN relative to the subject's own user namespace rather than\nthe init user namespace, so with the default\nunprivileged_userns_apparmor_policy=1 the path is reachable from an\nunprivileged task in a matched-level nested namespace, not only by a\nglobally privileged one.\n\nPerform the addition in u64 so that it cannot wrap, restoring the\nintended i + cnt < sets.size guarantee.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-17 17:17:20","updated_at":"2026-09-17 17:17:20"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/ef79a405f83993f0fda5efde371d98433f7d7a47","name":"https://git.kernel.org/stable/c/ef79a405f83993f0fda5efde371d98433f7d7a47","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/465946d3c560c0137e6a180ba054dddc4d049f5a","name":"https://git.kernel.org/stable/c/465946d3c560c0137e6a180ba054dddc4d049f5a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90246","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90246","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3d28e2397af7a89ac3de33c686ed404cda59b5d5 ef79a405f83993f0fda5efde371d98433f7d7a47 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3d28e2397af7a89ac3de33c686ed404cda59b5d5 465946d3c560c0137e6a180ba054dddc4d049f5a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.0","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.6 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["security/apparmor/policy_unpack.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"ef79a405f83993f0fda5efde371d98433f7d7a47","status":"affected","version":"3d28e2397af7a89ac3de33c686ed404cda59b5d5","versionType":"git"},{"lessThan":"465946d3c560c0137e6a180ba054dddc4d049f5a","status":"affected","version":"3d28e2397af7a89ac3de33c686ed404cda59b5d5","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["security/apparmor/policy_unpack.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.0"},{"lessThan":"7.0","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.6","versionStartIncluding":"7.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"7.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix integer overflow in verify_tags() bounds check\n\nverify_tags() validates the tagset table unpacked from a policy blob.\nFor each set it reads a count and checks that advancing the index by\nthat count stays inside sets.table[]:\n\n\tu32 cnt = tags->sets.table[i];\n\n\tif (i+cnt >= tags->sets.size) {\n\ni, cnt and sets.size are all u32, so i+cnt is evaluated modulo 2^32.\nsets.table[] is filled by unpack_tagsets() with aa_unpack_u32(), so\nevery entry is a raw unbounded 32-bit word taken from the policy blob,\nand verify_tags() is the function that is supposed to validate it.  A\ncount close to U32_MAX makes the sum wrap to a small value, the guard\npasses, and the inner loop then walks sets.table[++i] past the end of\nthe kcalloc(size, sizeof(u32)) allocation.\n\nNote that sets.size is bounded by 65535, because unpack_tagsets() reads\nit with aa_unpack_array() as a u16, so the wrap cannot be reached by\ngrowing the table; it is reached purely through the attacker-supplied\ncount.\n\nWith sets.size = 2 and sets.table = { 0, 0xffffffff }:\n\n  i = 0: cnt = 0, guard 0 + 0 >= 2 is false, inner loop does not run\n  i = 1: cnt = 0xffffffff, guard (1 + 0xffffffff) mod 2^32 == 0 >= 2 is\n         false, so the guard is bypassed and the inner loop reads\n         sets.table[2] -- one element past a two element allocation\n\nThe walk continues until an out-of-bounds value happens to be >=\nhdrs.size or the access faults, so a crafted policy yields an\nout-of-bounds read on the policy load path\n(aa_replace_profiles -> aa_unpack -> unpack_policydb -> unpack_tags ->\nverify_tags).  unpack_tags() runs before the perms and DFA tables are\nunpacked, so no other table needs to be well formed to reach it.\n\nPolicy load is gated by aa_may_manage_policy(), which checks\nCAP_MAC_ADMIN relative to the subject's own user namespace rather than\nthe init user namespace, so with the default\nunprivileged_userns_apparmor_policy=1 the path is reachable from an\nunprivileged task in a matched-level nested namespace, not only by a\nglobally privileged one.\n\nPerform the addition in u64 so that it cannot wrap, restoring the\nintended i + cnt < sets.size guarantee."}],"providerMetadata":{"dateUpdated":"2026-09-17T16:07:48.524Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/ef79a405f83993f0fda5efde371d98433f7d7a47"},{"url":"https://git.kernel.org/stable/c/465946d3c560c0137e6a180ba054dddc4d049f5a"}],"title":"apparmor: fix integer overflow in verify_tags() bounds check","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-90246","datePublished":"2026-09-17T16:07:48.524Z","dateReserved":"2026-09-11T19:38:34.795Z","dateUpdated":"2026-09-17T16:07:48.524Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-17 17:17:20","lastModifiedDate":"2026-09-17 17:17:20","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"90246","Ordinal":"1","Title":"apparmor: fix integer overflow in verify_tags() bounds check","CVE":"CVE-2026-90246","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"90246","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix integer overflow in verify_tags() bounds check\n\nverify_tags() validates the tagset table unpacked from a policy blob.\nFor each set it reads a count and checks that advancing the index by\nthat count stays inside sets.table[]:\n\n\tu32 cnt = tags->sets.table[i];\n\n\tif (i+cnt >= tags->sets.size) {\n\ni, cnt and sets.size are all u32, so i+cnt is evaluated modulo 2^32.\nsets.table[] is filled by unpack_tagsets() with aa_unpack_u32(), so\nevery entry is a raw unbounded 32-bit word taken from the policy blob,\nand verify_tags() is the function that is supposed to validate it.  A\ncount close to U32_MAX makes the sum wrap to a small value, the guard\npasses, and the inner loop then walks sets.table[++i] past the end of\nthe kcalloc(size, sizeof(u32)) allocation.\n\nNote that sets.size is bounded by 65535, because unpack_tagsets() reads\nit with aa_unpack_array() as a u16, so the wrap cannot be reached by\ngrowing the table; it is reached purely through the attacker-supplied\ncount.\n\nWith sets.size = 2 and sets.table = { 0, 0xffffffff }:\n\n  i = 0: cnt = 0, guard 0 + 0 >= 2 is false, inner loop does not run\n  i = 1: cnt = 0xffffffff, guard (1 + 0xffffffff) mod 2^32 == 0 >= 2 is\n         false, so the guard is bypassed and the inner loop reads\n         sets.table[2] -- one element past a two element allocation\n\nThe walk continues until an out-of-bounds value happens to be >=\nhdrs.size or the access faults, so a crafted policy yields an\nout-of-bounds read on the policy load path\n(aa_replace_profiles -> aa_unpack -> unpack_policydb -> unpack_tags ->\nverify_tags).  unpack_tags() runs before the perms and DFA tables are\nunpacked, so no other table needs to be well formed to reach it.\n\nPolicy load is gated by aa_may_manage_policy(), which checks\nCAP_MAC_ADMIN relative to the subject's own user namespace rather than\nthe init user namespace, so with the default\nunprivileged_userns_apparmor_policy=1 the path is reachable from an\nunprivileged task in a matched-level nested namespace, not only by a\nglobally privileged one.\n\nPerform the addition in u64 so that it cannot wrap, restoring the\nintended i + cnt < sets.size guarantee.","Type":"Description","Title":"apparmor: fix integer overflow in verify_tags() bounds check"}]}}}