{"cve":"CVE-2026-23407","nvd":{"published":"2026-04-01T09:16:16.527","modified":"2026-06-17T10:21:31.340","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\napparmor: fix missing bounds check on DEFAULT table in verify_dfa()\n\nThe verify_dfa() function only checks DEFAULT_TABLE bounds when the state\nis not differentially encoded.\n\nWhen the verification loop traverses the differential encoding chain,\nit reads k = DEFAULT_TABLE[j] and uses k as an array index without\nvalidation. A malformed DFA with DEFAULT_TABLE[j] >= state_count,\ntherefore, causes both out-of-bounds reads and writes.\n\n[   57.179855] ==================================================================\n[   57.180549] BUG: KASAN: slab-out-of-bounds in verify_dfa+0x59a/0x660\n[   57.180904] Read of size 4 at addr ffff888100eadec4 by task su/993\n\n[   57.181554] CPU: 1 UID: 0 PID: 993 Comm: su Not tainted 6.19.0-rc7-next-20260127 #1 PREEMPT(lazy)\n[   57.181558] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   57.181563] Call Trace:\n[   57.181572]  <TASK>\n[   57.181577]  dump_stack_lvl+0x5e/0x80\n[   57.181596]  print_report+0xc8/0x270\n[   57.181605]  ? verify_dfa+0x59a/0x660\n[   57.181608]  kasan_report+0x118/0x150\n[   57.181620]  ? verify_dfa+0x59a/0x660\n[   57.181623]  verify_dfa+0x59a/0x660\n[   57.181627]  aa_dfa_unpack+0x1610/0x1740\n[   57.181629]  ? __kmalloc_cache_noprof+0x1d0/0x470\n[   57.181640]  unpack_pdb+0x86d/0x46b0\n[   57.181647]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   57.181653]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   57.181656]  ? aa_unpack_nameX+0x1a8/0x300\n[   57.181659]  aa_unpack+0x20b0/0x4c30\n[   57.181662]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   57.181664]  ? stack_depot_save_flags+0x33/0x700\n[   57.181681]  ? kasan_save_track+0x4f/0x80\n[   57.181683]  ? kasan_save_track+0x3e/0x80\n[   57.181686]  ? __kasan_kmalloc+0x93/0xb0\n[   57.181688]  ? __kvmalloc_node_noprof+0x44a/0x780\n[   57.181693]  ? aa_simple_write_to_buffer+0x54/0x130\n[   57.181697]  ? policy_update+0x154/0x330\n[   57.181704]  aa_replace_profiles+0x15a/0x1dd0\n[   57.181707]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   57.181710]  ? __kvmalloc_node_noprof+0x44a/0x780\n[   57.181712]  ? aa_loaddata_alloc+0x77/0x140\n[   57.181715]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   57.181717]  ? _copy_from_user+0x2a/0x70\n[   57.181730]  policy_update+0x17a/0x330\n[   57.181733]  profile_replace+0x153/0x1a0\n[   57.181735]  ? rw_verify_area+0x93/0x2d0\n[   57.181740]  vfs_write+0x235/0xab0\n[   57.181745]  ksys_write+0xb0/0x170\n[   57.181748]  do_syscall_64+0x8e/0x660\n[   57.181762]  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n[   57.181765] RIP: 0033:0x7f6192792eb2\n\nRemove the MATCH_FLAG_DIFF_ENCODE condition to validate all DEFAULT_TABLE\nentries unconditionally.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/22094c996968a7c5b59cd3fc9fcbdfdd46d02fec","https://git.kernel.org/stable/c/555829fd91eaf0711e369b0a92aecb0f0aa3281f","https://git.kernel.org/stable/c/5a68e46dfe0c8c8ffc6f425ebc4cae6238566ecc","https://git.kernel.org/stable/c/76b4d36c5122866452d34d8f79985e191f9c3831","https://git.kernel.org/stable/c/7c7cf05e0606f554c467e3a4dc49e2e578a755b4"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:28:18.033120106+00:00"},"epss":{"cve":"CVE-2026-23407","score":0.00184,"percentile":0.08033,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}