{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90294","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.798Z","datePublished":"2026-09-17T16:08:20.664Z","dateUpdated":"2026-09-18T17:54:24.543Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-18T17:54:24.543Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nIB/isert: delay the final Login Response until the session is registered\n\nisert_put_login_tx() puts the final Login Response on the wire before\n__transport_register_session(), which iscsi_post_login_handler() reaches\nonly after iscsi_target_do_login() returns.  An initiator that issues a\nSCSI command as soon as it sees that response can have it executed against\nan se_session whose se_tpg is still NULL, and the ib-comp-wq worker oopses\non the NULL dereference.\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f]\n CPU: 0 UID: 0 PID: 178 Comm: kworker/0:1H Not tainted 7.2.0-rc5-V2CTL-gf5098b6bae76 #10 PREEMPT(lazy)\n 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 Workqueue: ib-comp-wq ib_cq_poll_work\n RIP: 0010:target_submit+0xbe/0x390\n Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 89 02 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 64 24 18 49 8d 7c 24 78 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 5a 02 00 00 48 8d 7b 78 4d 8b 6c 24 78 48 b8 00\n RSP: 0018:ffff8881058cfa78 EFLAGS: 00010206\n RAX: dffffc0000000000 RBX: ffff88810c78c6f0 RCX: ffffffff964bb363\n RDX: 000000000000000f RSI: 00000000fffffe00 RDI: 0000000000000078\n RBP: 1ffff11020b19f52 R08: 0000000000000001 R09: ffffed1020b19f52\n R10: 0000000000000003 R11: ffff88810596c000 R12: 0000000000000000\n R13: ffff88810c61b000 R14: ffff88810c6a3400 R15: ffff88810c61b044\n FS:  0000000000000000(0000) GS:ffff8881822b2000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f1f1b83c000 CR3: 000000006fe72001 CR4: 0000000000770ef0\n PKRU: 55555554\n Call Trace:\n  <TASK>\n  ? __pfx__raw_spin_lock_bh+0x10/0x10\n  ? __pfx_target_submit+0x10/0x10\n  ? mutex_lock+0x81/0xe0\n  ? __pfx_mutex_lock+0x10/0x10\n  ? iscsit_execute_cmd+0x650/0x850\n  iscsit_sequence_cmd+0x186/0x3d0\n  iscsit_process_scsi_cmd+0x87/0x300\n  isert_recv_done+0x1002/0x2390\n  ? __pfx_isert_recv_done+0x10/0x10\n  ? rxe_poll_cq+0x253/0x3d0\n  ? finish_task_switch.isra.0+0x1dc/0xa70\n  __ib_process_cq+0xe1/0x390\n  ib_cq_poll_work+0x46/0x150\n  process_one_work+0x633/0x1030\n  ? assign_work+0x11d/0x370\n  worker_thread+0x45b/0xd10\n  ? __pfx_worker_thread+0x10/0x10\n  ? __pfx_worker_thread+0x10/0x10\n  kthread+0x2c6/0x3b0\n  ? recalc_sigpending+0x15c/0x1e0\n  ? __pfx_kthread+0x10/0x10\n  ret_from_fork+0x36e/0x5a0\n  ? __pfx_ret_from_fork+0x10/0x10\n  ? __switch_to+0x572/0xdd0\n  ? __pfx_kthread+0x10/0x10\n  ret_from_fork_asm+0x1a/0x30\n  </TASK>\n Modules linked in:\n ---[ end trace 0000000000000000 ]---\n\nDelay the final Login Response instead.  isert_get_rx_pdu() runs from\niscsi_target_rx_thread() after conn->rx_login_comp, completed by\niscsi_post_login_handler() after __transport_register_session(); iscsi-TCP\nand cxgbit already take PDUs from that thread, isert alone does not.  The\nbuffers are still posted first, so the initiator's first command does not\nmeet an empty receive queue and nothing depends on RNR flow control, and\nthe header and payload live in isert_conn, not in the struct iscsi_login\nthat iscsi_target_nego_release() frees first.\n\nOver rxe, 400 login cycles per run, the oops appeared in 10 of 20\nunpatched runs and in none of 20 runs with this patch.  An\ninitiator that never waits is handled by the next patch.\n\nNot tested: iWARP, discovery sessions over iSER, and real HCAs."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - The trigger is an ISCSI_OP_SCSI_CMD RDMA SEND handled by isert_recv_done after isert_put_login_tx already posted the final Login Response; those PDUs arrive from a remote initiator on the QP accepted by isert_connect_request after rdma_listen() in isert_setup_id, which binds RoCEv2 (UDP/IP) or iWARP (TCP).\nAC:L - The initiator completes login so isert_put_login_tx posts RX buffers and sends the Login Response, then immediately sends a SCSI command that isert_recv_done runs on ib-comp-wq before iscsi_post_login_handler calls __transport_register_session; the attacker controls both sides of that window and can retry.\nPR:N - login->login_complete is set in iscsi_target_do_login CSG1 only after iscsi_conn_authenticated(); when tpg_attrib.authentication is 0, iscsi_handle_authentication() accepts AuthMethod=None with no secret, and generate_node_acls demo mode lets core_tpg_check_initiator_node_acl() admit a client-asserted InitiatorName.\nUI:N - The attacker is the iSER initiator that finishes login and posts the SCSI command on its own QP; no local user or administrator action is required.\nS:U - The NULL se_sess->se_tpg load in target_submit() oopses the same kernel that runs ib_isert; no VM, IOMMU, or sandbox boundary is crossed.\nC:N - transport_alloc_session() kmem_cache_zallocs se_session so se_tpg stays NULL until __transport_register_session(); target_submit() only loads se_tpg->se_tpg_tfo and takes a GPF, with no out-of-bounds read.\nI:N - The fault is a NULL load of se_cmd->se_sess->se_tpg in target_submit(); this path does not write kernel memory or reuse a freed object.\nA:H - KASAN reports a null-ptr-deref in target_submit() on ib-comp-wq (ib_cq_poll_work → isert_recv_done → iscsit_process_scsi_cmd → iscsit_execute_cmd), producing a kernel oops."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/ulp/isert/ib_isert.c","drivers/infiniband/ulp/isert/ib_isert.h"],"versions":[{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"e148dbac43308d9e4313070bfc5b355d03134809","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"a18fb8d540b3e631cb7e50e55f3c462c05b3a114","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"0d2efc355982064855f24f73f9fbb6c65ca4a5c7","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"f84e9adf4d9f4c0c79ef4a7d9e0c5c08b1337033","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"11694889c4bab47047a60690ceb70d7551ed5b2e","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"a6c19af05c170f267eca1d01c3c72c84ba7860ae","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"4397ea31e3b0d017c2b9b876b326df0b3eb845bf","status":"affected","versionType":"git"},{"version":"b8d26b3be8b33682cf163274ed07479a70554633","lessThan":"464f5afa92d071a226f88424803b0fcf88093ede","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/ulp/isert/ib_isert.c","drivers/infiniband/ulp/isert/ib_isert.h"],"versions":[{"version":"3.10","status":"affected"},{"version":"0","lessThan":"3.10","status":"unaffected","versionType":"semver"},{"version":"5.10.270","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.221","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.188","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.52","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.10","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/e148dbac43308d9e4313070bfc5b355d03134809"},{"url":"https://git.kernel.org/stable/c/a18fb8d540b3e631cb7e50e55f3c462c05b3a114"},{"url":"https://git.kernel.org/stable/c/0d2efc355982064855f24f73f9fbb6c65ca4a5c7"},{"url":"https://git.kernel.org/stable/c/f84e9adf4d9f4c0c79ef4a7d9e0c5c08b1337033"},{"url":"https://git.kernel.org/stable/c/11694889c4bab47047a60690ceb70d7551ed5b2e"},{"url":"https://git.kernel.org/stable/c/a6c19af05c170f267eca1d01c3c72c84ba7860ae"},{"url":"https://git.kernel.org/stable/c/4397ea31e3b0d017c2b9b876b326df0b3eb845bf"},{"url":"https://git.kernel.org/stable/c/464f5afa92d071a226f88424803b0fcf88093ede"}],"title":"IB/isert: delay the final Login Response until the session is registered","x_generator":{"engine":"bippy-1.2.0"}}}}