{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89482","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.712Z","datePublished":"2026-09-11T19:43:37.236Z","dateUpdated":"2026-09-14T12:00:19.222Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-14T12:00:19.222Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvme-tcp: do not accept C2HData based on blk_rq_payload_bytes() alone\n\nCommit 25e5cb780e62 (\"nvme-tcp: fix possible crash in write_zeroes\nprocessing\") established that blk_rq_payload_bytes() must not be read\nwithout first checking blk_rq_nr_phys_segments(), and recorded the\nresult in nvme_tcp_setup_cmd_pdu() as req->data_len. The receive side\nwas left as it was.\n\nThe two differ for REQ_OP_WRITE_ZEROES, which has no physical segments\nbut a non-zero blk_rq_bytes(), so setup leaves req->iter untouched\nwhile the receive gate lets a C2HData through and nvme_tcp_recv_data()\ncopies into whatever the previous command on that tag left there. The\ndriver-private area is zeroed only when the tag set is allocated.\n\nReproduced with a test target that leaves a residual iterator on a tag\nand then sends a C2HData for a WRITE_ZEROES command on the same tag:\n\nBUG: KASAN: wild-memory-access in _copy_to_iter+0x642/0x1330\nWrite of size 512 at addr ffe728c2175dfa81 by task kworker/0:1H/103\n\nCPU: 0 UID: 0 PID: 103 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMETCP-gf5098b6bae76 #1 PREEMPT(lazy)\nHardware 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\nWorkqueue: nvme_tcp_wq nvme_tcp_io_work\nCall Trace:\n <TASK>\n dump_stack_lvl+0x53/0x70\n kasan_report+0xce/0x100\n ? _copy_to_iter+0x642/0x1330\n kasan_check_range+0x105/0x1b0\n __asan_memcpy+0x3c/0x60\n _copy_to_iter+0x642/0x1330\n ? __pfx_sock_has_perm+0x10/0x10\n ? worker_thread+0x45b/0xd10\n ? __pfx__copy_to_iter+0x10/0x10\n ? _raw_spin_lock_bh+0x83/0xe0\n ? __pfx__raw_spin_lock_bh+0x10/0x10\n __skb_datagram_iter+0xf3/0x820\n ? __pfx_simple_copy_to_iter+0x10/0x10\n ? __asan_memcpy+0x3c/0x60\n ? skb_copy_bits+0x58d/0x830\n skb_copy_datagram_iter+0x37/0x120\n nvme_tcp_recv_skb+0xa07/0x4320\n ? __pfx_nvme_tcp_recv_skb+0x10/0x10\n __tcp_read_sock+0x1ab/0x810\n ? __pfx_nvme_tcp_recv_skb+0x10/0x10\n ? __pfx_lock_sock_nested+0x10/0x10\n ? __pfx___tcp_read_sock+0x10/0x10\n nvme_tcp_try_recv+0x152/0x1e0\n ? __pfx_nvme_tcp_try_recv+0x10/0x10\n ? __pfx_mutex_unlock+0x10/0x10\n nvme_tcp_io_work+0x1e4/0x6c0\n ? __schedule+0x181a/0x49f0\n ? __pfx_nvme_tcp_io_work+0x10/0x10\n process_one_work+0x633/0x1030\n\nKeep the blk_rq_payload_bytes() test and add req->data_len to it. The\nold test is what rejects a C2HData naming a tag that is no longer in\nflight, because blk_update_request() zeroes rq->__data_len on\ncompletion; req->data_len and req->curr_bio are driver-private and\nsurvive completion, so they cannot stand in for it. Setup initialises\nthe iterator only when both req->curr_bio and req->data_len are set, so\nthe gate now tests the same two."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The nvme-tcp host receive path parses C2HData PDUs from a remote NVMe/TCP target over a routable TCP connection (typically port 4420); a malicious or compromised target, or an on-path attacker injecting into the stream, triggers the bug from the network.\nAC:L - A malicious target can advertise WRITE_ZEROES, wait for tag reuse after a data command, and send C2HData for that in-flight WRITE_ZEROES; leftover iterator state is deterministic because driver-private fields are not cleared on reuse, so no race or memory-layout luck is required.\nPR:N - NVMe/TCP authentication (TLS, DH-HMAC-CHAP) is optional and off by default; the vulnerable copy runs on C2HData from the connected peer, which needs no credentials or privileges on the victim host.\nUI:N - Once the host is connected to the target as persistent storage, ordinary filesystem and block I/O generate WRITE_ZEROES commands; the attacker sends the crafted PDU without any further victim action.\nS:U - The stale-iterator write corrupts memory in the same host kernel security authority; this is not a VM, IOMMU, or sandbox boundary crossing.\nC:H - nvme_tcp_recv_data() writes attacker-controlled C2HData through a leftover iov_iter into pages from a previously completed command on the same tag, a use-after-free of those buffers that can be turned into an arbitrary read via heap reuse.\nI:H - The copy is a use-after-free / wild write of attacker-chosen contents and length into reused kernel or page-cache memory, which is exploitable for arbitrary write and control-flow hijacking.\nA:H - The same stale-iterator write was reproduced as a KASAN wild-memory-access in _copy_to_iter from nvme_tcp_io_work and can oops or panic the host kernel."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/nvme/host/tcp.c"],"versions":[{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"32ea8ce96b9bd797c59c351ce490ffd97adaa8c0","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"dd8906bb8f8d5bf1c9f861e1382c82b87bfe7cab","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"7ed0b61bbc145988be292c4d3ec580aebd8d2bcd","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"b96e1ff75e5c0ad6e077ac002b1d30b0a2b49528","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"b36161701cb366f416afdcf70771d432a7c74753","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"6a01b58263108eaf9869bb6f82f07709240c6589","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"641ad3a30ba560f0a9a610376c568d7b75d2a2aa","status":"affected","versionType":"git"},{"version":"25e5cb780e62bde432b401f312bb847edc78b432","lessThan":"3a4aa9e6ad3e35f8e24d5eaf38ee4d437075fb36","status":"affected","versionType":"git"},{"version":"f507ae6e33cbe56c4e3fe000434fc0ecc263d098","status":"affected","versionType":"git"},{"version":"b1458c16f4e26e87492e58e4d24a1873bd09232a","status":"affected","versionType":"git"},{"version":"5.4.36","lessThan":"5.5","status":"affected","versionType":"semver"},{"version":"5.6.8","lessThan":"5.7","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/tcp.c"],"versions":[{"version":"5.7","status":"affected"},{"version":"0","lessThan":"5.7","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-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":"5.7","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.12.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.3-rc1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.36"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6.8"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/32ea8ce96b9bd797c59c351ce490ffd97adaa8c0"},{"url":"https://git.kernel.org/stable/c/dd8906bb8f8d5bf1c9f861e1382c82b87bfe7cab"},{"url":"https://git.kernel.org/stable/c/7ed0b61bbc145988be292c4d3ec580aebd8d2bcd"},{"url":"https://git.kernel.org/stable/c/b96e1ff75e5c0ad6e077ac002b1d30b0a2b49528"},{"url":"https://git.kernel.org/stable/c/b36161701cb366f416afdcf70771d432a7c74753"},{"url":"https://git.kernel.org/stable/c/6a01b58263108eaf9869bb6f82f07709240c6589"},{"url":"https://git.kernel.org/stable/c/641ad3a30ba560f0a9a610376c568d7b75d2a2aa"},{"url":"https://git.kernel.org/stable/c/3a4aa9e6ad3e35f8e24d5eaf38ee4d437075fb36"}],"title":"nvme-tcp: do not accept C2HData based on blk_rq_payload_bytes() alone","x_generator":{"engine":"bippy-1.2.0"}}}}