{"id":"CVE-2026-23269","state":"PUBLISHED","title":"apparmor: validate DFA start states are in bounds in unpack_pdb","description":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: validate DFA start states are in bounds in unpack_pdb\n\nStart states are read from untrusted data and used as indexes into the\nDFA state tables. The aa_dfa_next() function call in unpack_pdb() will\naccess dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds\nthe number of states in the DFA, this results in an out-of-bound read.\n\n==================================================================\n BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360\n Read of size 4 at addr ffff88811956fb90 by task su/1097\n ...\n\nReject policies with out-of-bounds start states during unpacking\nto prevent the issue.","publishedAt":"2026-03-18T17:54:42.988Z","updatedAt":"2026-08-05T12:20:59.546Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"f43eea8ae0102ea198da211ef7f5ce83725ecf19","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"5487871b2b56c19d26936ed6fdc62652b30941df","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"5443c027ec16afa55b1b8a3e7a1ab2ea3c77767a","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"07cf6320f40ea2ccfad63728cff34ecb309d03da","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"15c3eb8916e7db01cb246d04a1fe6f0fdc065b0c","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"0baadb0eece2c4d939db10d3c323b4652ac79a58","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"3bb7db43e32190c973d4019037cedb7895920184","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"9063d7e2615f4a7ab321de6b520e23d370e58816","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/policy_unpack.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.4","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.169","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.77","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.18","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.8","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":["security/apparmor/policy_unpack.c"]}],"references":["https://git.kernel.org/stable/c/f43eea8ae0102ea198da211ef7f5ce83725ecf19","https://git.kernel.org/stable/c/5487871b2b56c19d26936ed6fdc62652b30941df","https://git.kernel.org/stable/c/5443c027ec16afa55b1b8a3e7a1ab2ea3c77767a","https://git.kernel.org/stable/c/07cf6320f40ea2ccfad63728cff34ecb309d03da","https://git.kernel.org/stable/c/15c3eb8916e7db01cb246d04a1fe6f0fdc065b0c","https://git.kernel.org/stable/c/0baadb0eece2c4d939db10d3c323b4652ac79a58","https://git.kernel.org/stable/c/3bb7db43e32190c973d4019037cedb7895920184","https://git.kernel.org/stable/c/9063d7e2615f4a7ab321de6b520e23d370e58816","https://www.qualys.com/2026/03/10/crack-armor.txt"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23269.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23269","state":"PUBLISHED","datePublished":"2026-03-18T17:54:42.988Z","dateUpdated":"2026-08-05T12:20:59.546Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:45.991Z"},"containers":{"cna":{"title":"apparmor: validate DFA start states are in bounds in unpack_pdb","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: validate DFA start states are in bounds in unpack_pdb\n\nStart states are read from untrusted data and used as indexes into the\nDFA state tables. The aa_dfa_next() function call in unpack_pdb() will\naccess dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds\nthe number of states in the DFA, this results in an out-of-bound read.\n\n==================================================================\n BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360\n Read of size 4 at addr ffff88811956fb90 by task su/1097\n ...\n\nReject policies with out-of-bounds start states during unpacking\nto prevent the issue."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"f43eea8ae0102ea198da211ef7f5ce83725ecf19","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"5487871b2b56c19d26936ed6fdc62652b30941df","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"5443c027ec16afa55b1b8a3e7a1ab2ea3c77767a","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"07cf6320f40ea2ccfad63728cff34ecb309d03da","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"15c3eb8916e7db01cb246d04a1fe6f0fdc065b0c","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"0baadb0eece2c4d939db10d3c323b4652ac79a58","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"3bb7db43e32190c973d4019037cedb7895920184","versionType":"git"},{"version":"ad5ff3db53c68c2f12936bc74ea5dfe0af943592","status":"affected","lessThan":"9063d7e2615f4a7ab321de6b520e23d370e58816","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["security/apparmor/policy_unpack.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.4","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.169","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.77","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.18","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.8","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":["security/apparmor/policy_unpack.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/f43eea8ae0102ea198da211ef7f5ce83725ecf19"},{"url":"https://git.kernel.org/stable/c/5487871b2b56c19d26936ed6fdc62652b30941df"},{"url":"https://git.kernel.org/stable/c/5443c027ec16afa55b1b8a3e7a1ab2ea3c77767a"},{"url":"https://git.kernel.org/stable/c/07cf6320f40ea2ccfad63728cff34ecb309d03da"},{"url":"https://git.kernel.org/stable/c/15c3eb8916e7db01cb246d04a1fe6f0fdc065b0c"},{"url":"https://git.kernel.org/stable/c/0baadb0eece2c4d939db10d3c323b4652ac79a58"},{"url":"https://git.kernel.org/stable/c/3bb7db43e32190c973d4019037cedb7895920184"},{"url":"https://git.kernel.org/stable/c/9063d7e2615f4a7ab321de6b520e23d370e58816"},{"url":"https://www.qualys.com/2026/03/10/crack-armor.txt"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires writing to the local AppArmor policy interface at /sys/kernel/security/apparmor/.load, which is a local filesystem operation.\nAC:L - The attacker fully controls the crafted policy data containing the out-of-bounds start state values. No race condition or special conditions beyond the attacker's control are needed.\nPR:L - Loading AppArmor policy requires CAP_MAC_ADMIN, but since unprivileged_userns_apparmor_policy defaults to 1, an unprivileged local user can obtain this capability by creating a user namespace.\nUI:N - No user interaction is needed; the attacker can craft and load the malicious policy autonomously.\nS:U - The vulnerability operates within the kernel security scope; there is no crossing of a virtualization or sandbox boundary.\nC:H - The OOB read from slab memory uses an attacker-controlled offset (u32 start state) that is not bounded to a few bytes, allowing potential disclosure of arbitrary kernel heap data through cascading reads in match_char.\nI:N - This is strictly an out-of-bounds read vulnerability; there is no write primitive or direct data modification capability.\nA:H - The OOB slab read triggers a kernel crash/oops as confirmed by the KASAN report in the commit message, causing a denial of service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:20:59.546Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.1.169"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.12.77"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.18.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"6.19.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}