{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80789","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-26T14:34:25.793Z","datePublished":"2026-09-04T15:13:01.161Z","dateUpdated":"2026-09-04T15:13:01.161Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-04T15:13:01.161Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnvmet-tcp: bound SGL data length before allocating command buffers\n\nnvmet_tcp_map_data() reads the host-controlled 32-bit sgl->length\nand, for the in-capsule offset descriptor (type 0x01), checks it\nagainst port->inline_data_size before use. Any other SGL descriptor\ntype -- including the non-inline transport SGL data-block descriptor\n(type (NVME_TRANSPORT_SGL_DATA_DESC << 4) | NVME_SGL_FMT_TRANSPORT_A,\nthe type a real host uses for out-of-capsule writes) skips that check\nentirely and falls straight through to:\n\n\tcmd->req.sg = sgl_alloc(len, GFP_KERNEL, &cmd->req.sg_cnt);\n\nwith len taken directly from the wire, unbounded up to 4 GiB.\n\nnvmet_req_init() only parses the command and never inspects\nsgl->length, and nvmet_check_transfer_len() -- the only other place\ntransfer_len is validated -- runs later, from req->execute(), after\nthe allocation has already happened. For a write command the target\nresponds with an R2T and parks the command waiting for the host to\nsend the data; if the host (or an unauthenticated peer that simply\nnever follows up) never does, the sgl_alloc() buffer stays resident\nfor the life of the command. NVMe/TCP has no mandatory authentication\nin the default configuration, so any peer able to reach the target\nportal and complete a Fabrics connect can drive this with a single\ncrafted command, repeatable across queues and connections for\namplification. This is unbounded kernel memory allocation\ntriggered by a remote, effectively unauthenticated peer.\n\nValidate len against the same NVMET_TCP_MAXH2CDATA ceiling this file\nalready uses to bound per-PDU H2C data, for every SGL descriptor type,\nbefore doing any allocation. This closes the gap for the non-inline\ndescriptor while leaving the existing, tighter inline_data_size check\nin place for the in-capsule case.\n\nRuntime-verified on a v6.19 KASAN stand: with this bound in place, a\ncrafted write command carrying an oversized non-inline SGL length is\nrejected before sgl_alloc() runs, where the same request previously\ndrove an unbounded ~256 MiB kernel allocation (up to 4 GiB) that\nstayed resident pending an R2T the host never satisfies."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/nvme/target/tcp.c"],"versions":[{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"f6e51b09cbaa5f6f6e6a3a9dafa666f76c37aab5","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"f63e89a0310264264923f84406dea05fe752de62","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"0952541b153e258b99d39cdb03ea6919fdeb41d0","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"25ad03d5c0e858c4b63f1e4b6d461d2af1b30b22","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"d2acc96c528d589f5827cfb90e8e9229dd9d8cb4","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"6d27199ebe8cb223022150f74be13f154a964474","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"14dbe37681a6a7e346fc147bb363ec7cca3180a0","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"d895e66628f939edbb98608f6e033d3d39e6e546","status":"affected","versionType":"git"},{"version":"872d26a391da92ed8f0c0f5cb5fef428067b7f30","lessThan":"4a3f00262a044e8e15064b1a6860968bf0500bf4","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/nvme/target/tcp.c"],"versions":[{"version":"5.0","status":"affected"},{"version":"0","lessThan":"5.0","status":"unaffected","versionType":"semver"},{"version":"5.10.269","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.220","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.187","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.156","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.106","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.47","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.11","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2.1","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":"5.0","versionEndExcluding":"5.10.269"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"5.15.220"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.1.187"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.6.156"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.12.106"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.18.47"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"7.1.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"7.2.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f6e51b09cbaa5f6f6e6a3a9dafa666f76c37aab5"},{"url":"https://git.kernel.org/stable/c/f63e89a0310264264923f84406dea05fe752de62"},{"url":"https://git.kernel.org/stable/c/0952541b153e258b99d39cdb03ea6919fdeb41d0"},{"url":"https://git.kernel.org/stable/c/25ad03d5c0e858c4b63f1e4b6d461d2af1b30b22"},{"url":"https://git.kernel.org/stable/c/d2acc96c528d589f5827cfb90e8e9229dd9d8cb4"},{"url":"https://git.kernel.org/stable/c/6d27199ebe8cb223022150f74be13f154a964474"},{"url":"https://git.kernel.org/stable/c/14dbe37681a6a7e346fc147bb363ec7cca3180a0"},{"url":"https://git.kernel.org/stable/c/d895e66628f939edbb98608f6e033d3d39e6e546"},{"url":"https://git.kernel.org/stable/c/4a3f00262a044e8e15064b1a6860968bf0500bf4"}],"title":"nvmet-tcp: bound SGL data length before allocating command buffers","x_generator":{"engine":"bippy-1.2.0"}}}}