{"id":"CVE-2026-99153","summary":"scsi: libiscsi: Validate the ITT reflected in a Reject PDU","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: libiscsi: Validate the ITT reflected in a Reject PDU\n\nA Reject PDU carries a copy of the header it rejects, and\niscsi_handle_reject() takes the ITT out of that copy to find the task to\nclean up:\n\n      memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));\n      ...\n      task = iscsi_itt_to_task(conn, rejected_pdu.itt);\n\nThat value is whatever the target put there. iscsi_itt_to_task() bounds\nthe index against cmds_max and checks nothing else, so any task in the\npool can be named, and iscsi_nop_out_rsp() then completes it.\n\nAn index that has never been used gives a NULL task-\u003econn: the pool is\nzeroed at session setup and conn is assigned only when a task is\nallocated. If the task was used and returned, iscsi_complete_task() hits\nits WARN_ON_ONCE(task-\u003estate == ISCSI_TASK_FREE) and the refcount\nunderflows. An in-flight SCSI command is completed as successful - a 1\nMiB read returned 1048576 with none of its buffer written and no\nwarning.\n\nValidate the reflected ITT the way iscsi_itt_to_ctask() validates a\ncommand ITT, and require the task to be in flight and not a SCSI\ncommand.\n\n[    6.248477] Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI\n[    6.249357] KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]\n[    6.249951] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 7.2.0-rc5-ISCSI1-gf5098b6bae76 #1 PREEMPT(lazy)\n[    6.250718] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[    6.251616] RIP: 0010:iscsi_nop_out_rsp.constprop.0+0x46/0x160\n[    6.252043] Code: c1 ea 03 48 83 ec 08 80 3c 02 00 0f 85 f5 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 58 48 8d 7d 60 48 89 fa 48 c1 ea 03 \u003c80\u003e 3c 02 00 0f 85 c0 00 00 00 48 8b 45 60 48 39 c3 74 50 48 b8 00\n[    6.252813] RSP: 0018:ffff88806c907b80 EFLAGS: 00010206\n[    6.253042] RAX: dffffc0000000000 RBX: ffff88800607e000 RCX: ffffffff8d571a25\n[    6.253345] RDX: 000000000000000c RSI: ffff88806c907c38 RDI: 0000000000000060\n[    6.253642] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff235a504\n[    6.253947] R10: 0000000000000003 R11: 7463656e6e6f6320 R12: 0000000000000000\n[    6.254251] R13: 0000000000000000 R14: ffff88806c907c38 R15: 0000000000000000\n[    6.254549] FS:  0000000000000000(0000) GS:ffff8880d95bc000(0000) knlGS:0000000000000000\n[    6.254887] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[    6.255140] CR2: 00007fc393e8ffc0 CR3: 0000000005252006 CR4: 0000000000770ef0\n[    6.255439] PKRU: 55555554\n[    6.255564] Call Trace:\n[    6.255674]  \u003cIRQ\u003e\n[    6.255768]  __iscsi_complete_pdu+0x18bf/0x22a0\n[    6.256733]  iscsi_complete_pdu+0x54/0xa0\n[    6.256905]  iscsi_tcp_data_recv_done+0xf4/0x250\n[    6.257103]  iscsi_tcp_recv_skb+0x31e/0xec0\n[    6.257680]  iscsi_sw_tcp_recv+0x12f/0x390\n[    6.258061]  __tcp_read_sock+0x1ab/0x810\n[    6.258853]  iscsi_sw_tcp_data_ready+0x18b/0x510\n[    6.259808]  tcp_data_queue+0x1f13/0x4cd0\n[    6.260567]  tcp_rcv_established+0x8a5/0x3a00\n[    6.261931]  tcp_v4_do_rcv+0x449/0x960\n[    6.262269]  tcp_v4_rcv+0x2245/0x3bc0","modified":"2026-11-02T02:33:23.988691151Z","published":"2026-10-28T10:35:08.287Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99153.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/21ef746340ce246344f34278e205b8960c1d8874"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3637a4ad1d07477f1c60609876da6b60154d224b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/576125e7382a7826bd6c3c1ca4d9c582ed5be21d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7215a69b6456fda79c0935c2959045dff3fcaac8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c5958c770b2a0ee492414e26b07da9164a0d1f5d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d20583a9dbe0d32a9af8384c857c95c0fc115103"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d79343ae3223b3f7f74b55e79f8a1371fa3f4b1a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ebb8c5ef2aabf66895253600e8390e8fc7094807"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99153.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99153"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8afa1439fcff58da8f28c1d083046f229f6ab3de"},{"fixed":"3637a4ad1d07477f1c60609876da6b60154d224b"},{"fixed":"21ef746340ce246344f34278e205b8960c1d8874"},{"fixed":"d20583a9dbe0d32a9af8384c857c95c0fc115103"},{"fixed":"ebb8c5ef2aabf66895253600e8390e8fc7094807"},{"fixed":"576125e7382a7826bd6c3c1ca4d9c582ed5be21d"},{"fixed":"7215a69b6456fda79c0935c2959045dff3fcaac8"},{"fixed":"d79343ae3223b3f7f74b55e79f8a1371fa3f4b1a"},{"fixed":"c5958c770b2a0ee492414e26b07da9164a0d1f5d"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-99153.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.32"},{"fixed":"5.10.273"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.224"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.191"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.161"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.115"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.59"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-99153.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}