{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89483", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.712Z", "datePublished": "2026-09-11T19:43:38.076Z", "dateUpdated": "2026-10-19T08:47:33.684Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:47:33.684Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvme: zero the discard fallback page\n\nnvme_setup_discard() always maps sizeof(struct nvme_dsm_range) *\nNVME_DSM_MAX_RANGES = 4096 bytes as the DSM payload however many ranges\nthe command declares, because some devices ignore the 'Number of Ranges'\nfield - the Fixes: commit records two that read past the declared ranges.\nA single-range discard fills only the first 16 bytes.\n\nNormally the buffer comes from kzalloc() and the other 4080 bytes are\nzero. When that allocation fails the code falls back to the\nper-controller ctrl->discard_page, which nvme_init_ctrl() obtains with\nalloc_page(GFP_KERNEL) and nothing ever zeroes, so those 4080 bytes are\nwhatever the page last held and are handed to the controller. Reaching\nit requires the kzalloc(GFP_ATOMIC | __GFP_NOWARN) to fail, that is\nmemory pressure; it is not remotely triggerable. Failing the allocation\nunder KMSAN reproduces it, with the leaked tail full of vmemmap struct\npage pointers. The extent in the report is a partial transfer of the\npayload, not the whole 4096 bytes; the 16-byte boundary in it is the one\ndeclared range:\n\n[ 11.991601] BUG: KMSAN: uninit-value in dma_map_phys+0x14c8/0x1900\n[ 11.991969] dma_map_phys+0x14c8/0x1900\n[ 11.992220] dma_map_page_attrs+0xcf/0x130\n[ 11.992485] e1000_xmit_frame+0x4099/0x6d10\n[ 11.992768] dev_hard_start_xmit+0x22f/0xa80\n[ 11.993068] sch_direct_xmit+0x35c/0xcb0\n[ 11.993315] __dev_queue_xmit+0x1ee5/0x5eb0\n[ 11.993608] ip_finish_output2+0x1903/0x1c30\n[ 11.993881] ip_finish_output+0x288/0x870\n[ 11.994125] ip_output+0x15e/0x400\n[ 11.994365] __ip_queue_xmit+0x1e85/0x1fb0\n[ 11.994639] ip_queue_xmit+0x60/0x80\n[ 11.994899] __tcp_transmit_skb+0x4e71/0x5fa0\n[ 11.995210] tcp_write_xmit+0x3a36/0x9160\n[ 11.995533] __tcp_push_pending_frames+0xc5/0x3c0\n[ 11.995854] tcp_push+0x7dc/0x840\n[ 11.996076] tcp_sendmsg_locked+0x766c/0x8400\n[ 11.996371] tcp_sendmsg+0x4b/0x90\n[ 11.996572] inet_sendmsg+0x134/0x2a0\n[ 11.996823] __sock_sendmsg+0x265/0x360\n[ 11.997076] sock_sendmsg+0x100/0x1e0\n[ 11.997293] nvme_tcp_try_send+0x196f/0x6370\n[ 11.997605] nvme_tcp_queue_rq+0x1d54/0x20b0\n[ 11.997882] blk_mq_dispatch_rq_list+0x5ee/0x2e50\n[ 11.998175] __blk_mq_sched_dispatch_requests+0x16dc/0x24a0\n[ 11.998539] blk_mq_sched_dispatch_requests+0x11b/0x2c0\n[ 11.998865] blk_mq_run_work_fn+0x13b/0x280\n[ 11.999146] process_scheduled_works+0x966/0x1ad0\n[ 11.999465] worker_thread+0xe44/0x1480\n[ 11.999709] kthread+0x53b/0x600\n[ 11.999927] ret_from_fork+0x29f/0x7c0\n[ 12.000191] ret_from_fork_asm+0x1a/0x30\n[ 12.000460]\n[ 12.000558] Uninit was created at:\n[ 12.000788] __alloc_frozen_pages_noprof+0x8bf/0xd30\n[ 12.001096] alloc_pages_mpol+0x1d0/0x5f0\n[ 12.001326] alloc_pages_noprof+0x102/0x290\n[ 12.001627] nvme_init_ctrl+0x5a3/0x9f0\n[ 12.001891] nvme_tcp_create_ctrl+0xd75/0x19b0\n[ 12.002170] nvmf_dev_write+0x4c68/0x4fd0\n[ 12.002426] vfs_write+0x587/0x1a10\n[ 12.002636] __x64_sys_write+0x207/0x4f0\n[ 12.002874] x64_sys_call+0x2ff0/0x3ea0\n[ 12.003123] do_syscall_64+0x147/0x3b0\n[ 12.003400] entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[ 12.003680]\n[ 12.003777] Bytes 16-2843 of 2844 are uninitialized\n[ 12.004068] Memory access of size 2844 starts at ffff888109f82000\n[ 12.004412]\n[ 12.004530] CPU: 0 UID: 0 PID: 101 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMECTL-gf5098b6bae76 #1 PREEMPT(lazy)\n[ 12.005127] 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[ 12.005762] Workqueue: kblockd blk_mq_run_work_fn\n[ 12.006073] =====================================================\n\nAllocate the page with __GFP_ZERO. The single allocation site covers\nevery use of it: bytes no discard has written stay zero, and bytes one\ndid write hold that controller's own range list, which it has already\nbeen sent." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - nvme_setup_discard() DMA-maps a 4096-byte DSM buffer that nvme-tcp (KMSAN: nvme_tcp_try_send), nvme-rdma, and nvme-fc transmit to the remote controller, so a malicious NVMe-oF target on the storage fabric receives the leftover kernel page.\nAC:L - The fallback is used when kzalloc(GFP_ATOMIC|__GFP_NOWARN) fails; a fabric peer can drive watermarks with high queue-depth I/O while discards run and retry until discard_page is used, with no race or unknown layout required.\nPR:N - A compromised NVMe-oF target needs no Linux account or capability on the initiator; once the host is attached to fabric storage, DSM payloads are sent without further local authorization.\nUI:N - REQ_OP_DISCARD is issued automatically by mount-discard, fstrim timers, hole-punch, and thin-provision UNMAP during normal operation once an NVMe controller exists; no extra victim mount or click is required at exploit time.\nS:U - The disclosure is host kernel memory to the NVMe controller/peer within the same kernel authority and is not a VM escape, IOMMU bypass, or other cross-boundary scope change.\nC:H - nvme_init_ctrl() allocated discard_page with alloc_page(GFP_KERNEL) and no __GFP_ZERO, so up to 4080 bytes of stale buddy-page contents (KMSAN showed kernel/vmemmap pointers) are sent in the DSM payload, a page-sized leak rather than a few bounded bytes.\nI:N - The flaw only transmits leftover page bytes to the controller; it does not overwrite kernel objects, provide a write primitive, or enable control-flow hijacking.\nA:N - DMA/send of the uninitialized DSM padding completes without oops, panic, or hang; the KMSAN uninit-value report is a sanitizer finding on the transmit path, not a host denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/nvme/host/core.c" ], "versions": [ { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "76139b5bbf531e675934b97227be3521c7fdd537", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "3f84d2bd0d8ae8c7e8e0f8fc3cbf018a282971a1", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "415f2772ebcbc7f3f1ab1a71915dab82cee3465e", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "66b5af23b6f956e57f8205c46aa80b054631be34", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "dc4d4b70a863f7e39ef8bd137634be4e6db8b084", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "67551d8430df94c827e1830bd3a5fae1f66a5219", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "f5827817b4fc7feeabf4f53fb4b626e6edc52fef", "status": "affected", "versionType": "git" }, { "version": "530436c45ef2e446c12538a400e465929a0b3ade", "lessThan": "bededeaaeff404978a5a8e2a605a6c3017cddd3e", "status": "affected", "versionType": "git" }, { "version": "ffa56cbdd2409b522b4cb56461bea1c45889417b", "status": "affected", "versionType": "git" }, { "version": "8b0acb768a06083b0d28bace1481c1f6679e76f4", "status": "affected", "versionType": "git" }, { "version": "4.19.92", "lessThan": "4.20", "status": "affected", "versionType": "semver" }, { "version": "5.4.7", "lessThan": "5.5", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/nvme/host/core.c" ], "versions": [ { "version": "5.5", "status": "affected" }, { "version": "0", "lessThan": "5.5", "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": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "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": "5.5", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "7.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19.92" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4.7" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/76139b5bbf531e675934b97227be3521c7fdd537" }, { "url": "https://git.kernel.org/stable/c/3f84d2bd0d8ae8c7e8e0f8fc3cbf018a282971a1" }, { "url": "https://git.kernel.org/stable/c/415f2772ebcbc7f3f1ab1a71915dab82cee3465e" }, { "url": "https://git.kernel.org/stable/c/66b5af23b6f956e57f8205c46aa80b054631be34" }, { "url": "https://git.kernel.org/stable/c/dc4d4b70a863f7e39ef8bd137634be4e6db8b084" }, { "url": "https://git.kernel.org/stable/c/67551d8430df94c827e1830bd3a5fae1f66a5219" }, { "url": "https://git.kernel.org/stable/c/f5827817b4fc7feeabf4f53fb4b626e6edc52fef" }, { "url": "https://git.kernel.org/stable/c/bededeaaeff404978a5a8e2a605a6c3017cddd3e" } ], "title": "nvme: zero the discard fallback page", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-89483", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:22:40.450387Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:39.989Z" } } ] } }