{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98357", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.344Z", "datePublished": "2026-10-06T08:46:44.216Z", "dateUpdated": "2026-10-19T09:18:07.886Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:18:07.886Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nIB/isert: wait for deferred control PDU completions before releasing the connection\n\nisert_send_done() hands ISTATE_SEND_TASKMGTRSP, ISTATE_SEND_REJECT and\nISTATE_SEND_TEXTRSP completions off to isert_comp_wq and returns. The work\nitem then runs isert_completion_put() -> isert_put_cmd(), which reads\nisert_conn->conn and takes conn->cmd_lock.\n\nNothing orders that work item against teardown. isert_wait_conn() queues\nisert_release_work, which frees isert_conn, and iscsit_close_connection()\nfrees the iscsit_conn right after it returns, so the queued work can run\nagainst freed memory.\n\nCount the deferred control PDU completions per connection and let\nisert_wait_conn() wait for them before the release work is queued.\n\nISTATE_SEND_LOGOUTRSP is deliberately not counted: that branch runs\niscsit_logout_post_handler(), which ends up waiting for\nconn->conn_wait_comp, and that completion is only sent by\niscsit_close_connection() after it has called iscsit_wait_conn().\nWaiting for it here would deadlock. Its wait stays the existing\nisert_wait4logout().\n\nThe splat below is from a kernel with tracing printk()s and an msleep(200)\ninjected into isert_do_control_comp() to widen the window:\n\n BUG: KASAN: slab-use-after-free in isert_put_cmd+0x53d/0x620\n Read of size 8 at addr ffff8881054f1038 by task kworker/u17:1/182\n\n CPU: 0 UID: 0 PID: 182 Comm: kworker/u17:1 Tainted: G B 7.2.0-rc5-TWIDE-gb8babf08acc7 #1 PREEMPT(lazy)\n Tainted: [B]=BAD_PAGE\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: isert_comp_wq isert_do_control_comp\n Call Trace:\n \n dump_stack_lvl+0x53/0x70\n print_report+0xd0/0x630\n ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n ? _raw_spin_unlock_irqrestore+0x3e/0x70\n ? isert_put_cmd+0x53d/0x620\n kasan_report+0xce/0x100\n ? isert_put_cmd+0x53d/0x620\n isert_put_cmd+0x53d/0x620\n ? isert_completion_put+0x305/0x330\n ? isert_do_control_comp+0x2ef/0x310\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 \n\n Allocated by task 48:\n kasan_save_stack+0x33/0x60\n kasan_save_track+0x14/0x30\n __kasan_kmalloc+0x8f/0xa0\n __kmalloc_cache_noprof+0x158/0x370\n isert_cma_handler+0x1e3/0x2ae0\n cma_cm_event_handler+0x3e/0x240\n cma_ib_req_handler+0x17d9/0x4490\n cm_process_work+0x41/0x330\n cm_work_handler+0x5727/0xc160\n process_one_work+0x633/0x1030\n worker_thread+0x45b/0xd10\n kthread+0x2c6/0x3b0\n ret_from_fork+0x36e/0x5a0\n ret_from_fork_asm+0x1a/0x30\n\n Freed by task 184:\n kasan_save_stack+0x33/0x60\n kasan_save_track+0x14/0x30\n kasan_save_free_info+0x3b/0x60\n __kasan_slab_free+0x43/0x70\n kfree+0x121/0x380\n iscsit_close_connection+0x7cf/0x1e60\n iscsit_take_action_for_connection_exit+0x1b6/0x360\n iscsi_target_tx_thread+0x472/0x690\n kthread+0x2c6/0x3b0\n ret_from_fork+0x36e/0x5a0\n ret_from_fork_asm+0x1a/0x30" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The iSER initiator triggers it remotely over RDMA (iWARP/RoCEv2 are IP-routable). Its iSCSI Text Request (or a TMF or a malformed PDU that draws a Reject) makes isert_send_done() queue isert_do_control_comp(); an RDMA CM disconnect from the same initiator then starts teardown via iscsit_close_connection().\nAC:H - The attacker sends both the request and the disconnect, but the free only wins if the already-queued isert_comp_wq work stays delayed through ib_drain_qp, isert_wait4cmds and the release work. The attacker can't control that scheduling; the reporter needed an injected msleep(200) to reproduce it.\nPR:N - The attacker only needs a full-feature iSCSI session, and LIO allows login with AuthMethod=None, where the initiator IQN is merely asserted. No credentials are checked before the Text/TMF/Reject paths that queue the deferred completion.\nUI:N - The initiator triggers the response PDU and the connection teardown entirely through its own iSCSI PDUs and RDMA CM disconnect; no action by a target administrator is needed.\nS:U - The use-after-free is in the target host's own kernel memory (isert_conn and iscsit_conn), so the impact stays within the same kernel security authority.\nC:H - isert_put_cmd() dereferences the freed isert_conn->conn and reads the freed iscsit_conn and cmd structures. Reclaiming those slab objects lets attacker-shaped data steer kernel pointer reads.\nI:H - On the freed iscsit_conn, isert_put_cmd() takes spin_lock_bh(&conn->cmd_lock), runs list_del_init(&cmd->i_conn_node) and calls iscsit_release_cmd()/transport_generic_free_cmd(). These are writes and frees through freed memory, which can corrupt the heap.\nA:H - The isert_comp_wq worker hits a slab use-after-free in isert_put_cmd() (KASAN splat in the fix commit), which on production kernels can crash or oops the iSCSI target host." } ] } ], "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": "f5613acbe2e346d5c466ef0bd264fca936b69f82", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "ccdb1523f12bc8a9646de65055d1aafed9e9bcc6", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "0e230917670c6e6fe3243abfa11299fcbe05b1f4", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "505b242d9351690d1385bbe508ab4666f60363ce", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "7edb8a88d6c76237c8b4435765bee1009e26a50a", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "b96b8b3e41c308f606ffd10cfef1a7b9f97414cd", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "7908fbc597a694bbd99bfb59ece73bc3daded68e", "status": "affected", "versionType": "git" }, { "version": "b8d26b3be8b33682cf163274ed07479a70554633", "lessThan": "a8fe3dfce8c0d8a76dc3d8486a5bff5feebe156f", "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": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.54", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.8", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.18.54" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/f5613acbe2e346d5c466ef0bd264fca936b69f82" }, { "url": "https://git.kernel.org/stable/c/ccdb1523f12bc8a9646de65055d1aafed9e9bcc6" }, { "url": "https://git.kernel.org/stable/c/0e230917670c6e6fe3243abfa11299fcbe05b1f4" }, { "url": "https://git.kernel.org/stable/c/505b242d9351690d1385bbe508ab4666f60363ce" }, { "url": "https://git.kernel.org/stable/c/7edb8a88d6c76237c8b4435765bee1009e26a50a" }, { "url": "https://git.kernel.org/stable/c/b96b8b3e41c308f606ffd10cfef1a7b9f97414cd" }, { "url": "https://git.kernel.org/stable/c/7908fbc597a694bbd99bfb59ece73bc3daded68e" }, { "url": "https://git.kernel.org/stable/c/a8fe3dfce8c0d8a76dc3d8486a5bff5feebe156f" } ], "title": "IB/isert: wait for deferred control PDU completions before releasing the connection", "x_generator": { "engine": "bippy-1.2.0" } } } }