CVE-2026-31557 | Linux Kernel up to 6.12.79/6.18.20/6.19.10 nvmet nvmet_ctrl_free privilege escalation

VDB-359375 · CVE-2026-31557 · GCVE-0-2026-31557 LINUX KERNEL UP TO 6.12.79/6.18.20/6.19.10 NVMET NVMET_CTRL_FREE PRIVILEGE ESCALATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 4.4 $0-$5k 0.29+ Summaryinfo A vulnerability identified as critical has been detected in Linux Kernel up to 6.12.79/6.18.20/6.19.10. Impacted is the function nvmet_ctrl_free of the component nvmet. The manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2026-31557. No exploit is available. You should upgrade the affected component. Detailsinfo A vulnerability was found in Linux Kernel up to 6.12.79/6.18.20/6.19.10 and classified as critical. This issue affects the function nvmet_ctrl_free of the component nvmet. The impact remains unknown. The summary by CVE is: In the Linux kernel, the following vulnerability has been resolved: nvmet: move async event work off nvmet-wq For target nvmet_ctrl_free() flushes ctrl->async_event_work. If nvmet_ctrl_free() runs on nvmet-wq, the flush re-enters workqueue completion for the same worker:- A. Async event work queued on nvmet-wq (prior to disconnect): nvmet_execute_async_event() queue_work(nvmet_wq, &ctrl->async_event_work) nvmet_add_async_event() queue_work(nvmet_wq, &ctrl->async_event_work) B. Full pre-work chain (RDMA CM path): nvmet_rdma_cm_handler() nvmet_rdma_queue_disconnect() __nvmet_rdma_queue_disconnect() queue_work(nvmet_wq, &queue->release_work) process_one_work() lock((wq_completion)nvmet-wq) <--------- 1st nvmet_rdma_release_queue_work() C. Recursive path (same worker): nvmet_rdma_release_queue_work() nvmet_rdma_free_queue() nvmet_sq_destroy() nvmet_ctrl_put() nvmet_ctrl_free() flush_work(&ctrl->async_event_work) __flush_work() touch_wq_lockdep_map() lock((wq_completion)nvmet-wq) <--------- 2nd Lockdep splat: ============================================ WARNING: possible recursive locking detected 6.19.0-rc3nvme+ #14 Tainted: G N -------------------------------------------- kworker/u192:42/44933 is trying to acquire lock: ffff888118a00948 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x26/0x90 but task is already holding lock: ffff888118a00948 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x53e/0x660 3 locks held by kworker/u192:42/44933: #0: ffff888118a00948 ((wq_completion)nvmet-wq){+.+.}-{0:0}, at: process_one_work+0x53e/0x660 #1: ffffc9000e6cbe28 ((work_completion)(&queue->release_work)){+.+.}-{0:0}, at: process_one_work+0x1c5/0x660 #2: ffffffff82d4db60 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x62/0x530 Workqueue: nvmet-wq nvmet_rdma_release_queue_work [nvmet_rdma] Call Trace: __flush_work+0x268/0x530 nvmet_ctrl_free+0x140/0x310 [nvmet] nvmet_cq_put+0x74/0x90 [nvmet] nvmet_rdma_free_queue+0x23/0xe0 [nvmet_rdma] nvmet_rdma_release_queue_work+0x19/0x50 [nvmet_rdma] process_one_work+0x206/0x660 worker_thread+0x184/0x320 kthread+0x10c/0x240 ret_from_fork+0x319/0x390 Move async event work to a dedicated nvmet-aen-wq to avoid reentrant flush on nvmet-wq. It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-31557 since 03/09/2026. The exploitation is known to be difficult. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/24/2026). Upgrading to version 6.12.80, 6.18.21 or 6.19.11 eliminates this vulnerability. Applying the patch 49c7c50ee6325a084216e94395e067ecde8088fa/ca111c9d8d6c9d5735878d933a1716c4be86c2d1/25ceffc1dabec3b93f458b437aae26f4da293f87/2922e3507f6d5caa7f1d07f145e186fc6f317a4e is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version. Productinfo Type Operating System Vendor Linux Name Kernel Version 6.12.0 6.12.1 6.12.2 6.12.3 6.12.4 6.12.5 6.12.6 6.12.7 6.12.8 6.12.9 6.12.10 6.12.11 6.12.12 6.12.13 6.12.14 6.12.15 6.12.16 6.12.17 6.12.18 6.12.19 6.12.20 6.12.21 6.12.22 6.12.23 6.12.24 6.12.25 6.12.26 6.12.27 6.12.28 6.12.29 6.12.30 6.12.31 6.12.32 6.12.33 6.12.34 6.12.35 6.12.36 6.12.37 6.12.38 6.12.39 6.12.40 6.12.41 6.12.42 6.12.43 6.12.44 6.12.45 6.12.46 6.12.47 6.12.48 6.12.49 6.12.50 6.12.51 6.12.52 6.12.53 6.12.54 6.12.55 6.12.56 6.12.57 6.12.58 6.12.59 6.12.60 6.12.61 6.12.62 6.12.63 6.12.64 6.12.65 6.12.66 6.12.67 6.12.68 6.12.69 6.12.70 6.12.71 6.12.72 6.12.73 6.12.74 6.12.75 6.12.76 6.12.77 6.12.78 6.12.79 6.18.0 6.18.1 6.18.2 6.18.3 6.18.4 6.18.5 6.18.6 6.18.7 6.18.8 6.18.9 6.18.10 6.18.11 6.18.12 6.18.13 6.18.14 6.18.15 6.18.16 6.18.17 6.18.18 6.18.19 6.18.20 6.19.0 6.19.1 6.19.2 6.19.3 6.19.4 6.19.5 6.19.6 6.19.7 6.19.8 6.19.9 6.19.10 License open-source Website Vendor: https://www.kernel.org/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 4.6 VulDB Meta Temp Score: 4.4 VulDB Base Score: 4.6 VulDB Temp Score: 4.4 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Privilege escalation CWE: Unknown CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Partially Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Kernel 6.12.80/6.18.21/6.19.11 Patch: 49c7c50ee6325a084216e94395e067ecde8088fa/ca111c9d8d6c9d5735878d933a1716c4be86c2d1/25ceffc1dabec3b93f458b437aae26f4da293f87/2922e3507f6d5caa7f1d07f145e186fc6f317a4e Timelineinfo 03/09/2026 CVE reserved 04/24/2026 +45 days Advisory disclosed 04/24/2026 +0 days VulDB entry created 04/24/2026 +0 days VulDB entry last update Sourcesinfo Vendor: kernel.org Advisory: git.kernel.org Status: Confirmed CVE: CVE-2026-31557 (🔒) GCVE (CVE): GCVE-0-2026-31557 GCVE (VulDB): GCVE-100-359375 Entryinfo Created: 04/24/2026 17:43 Changes: 04/24/2026 17:43 (58) Complete: 🔍 Cache ID: 99:112:101 Discussion No comments yet. 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