{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98323", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.340Z", "datePublished": "2026-10-06T08:46:17.150Z", "dateUpdated": "2026-10-19T09:17:33.779Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:17:33.779Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/siw: Bound fragmented header copies by the remaining length\n\nsiw_get_hdr() can receive an extended DDP/RDMAP header across more than\none TCP callback. The first callback may receive most of the header,\nwhile the next one still limits the copy to hdrlen - MIN_DDP_HDR instead\nof the number of missing bytes. This makes the destination move past the\nend of the header and overwrite the receive state, including\nfpdu_part_rcvd. A later callback can then use a negative fpdu_part_rcvd\nvalue as a copy offset, which creates an OOB write.\n\nUse the number of header bytes already received when calculating the\nnext copy length." } ], "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 malformed input is the remote iWARP peer's own MPA/DDP/RDMAP header bytes on the siw TCP connection. The peer splits an extended header (e.g. RDMA Read Request, 44 bytes) across TCP segments, and siw_qp_llp_data_ready() -> tcp_read_sock() -> siw_tcp_rx_data() -> siw_get_hdr() parses them. The transport is routable TCP.\nAC:L - The peer fully controls TCP segmentation, so it can deterministically end a segment with fpdu_part_rcvd between 16 and hdrlen. The next segment then copies hdrlen-16 bytes at that offset. No race or state outside the attacker's control is involved beyond siw serving an iWARP listener.\nPR:N - Once the MPA exchange puts the QP in RTS, siw_get_hdr() parses every incoming FPDU header, and neither MPA nor DDP authenticates the peer. ULP authorisation (such as an nvmet-rdma host NQN check) only arrives in messages parsed by this same path, so the overflow fires before any credential check.\nUI:N - No victim action is needed. The attacker connects to the iWARP service and sends crafted fragmented FPDUs, and siw processes them in its sk_data_ready callback.\nS:U - The corruption is confined to kernel memory of the host running siw (struct siw_qp and its neighbours). That is the same security authority as the vulnerable component, with no VM or IOMMU boundary crossed.\nC:H - The overflow writes peer bytes over siw_rx_stream fields after hdr, including fpdu_part_rcvd. A negative fpdu_part_rcvd then makes skb_copy_bits() write to c_hdr plus an attacker-chosen offset. A controlled kernel write like this can be turned into arbitrary kernel memory disclosure.\nI:H - siw_get_hdr() copies up to hdrlen-17 attacker bytes past srx->hdr (27 for rreq), overwriting the receive state. The next callback uses the corrupted negative fpdu_part_rcvd as the destination offset of skb_copy_bits(), giving an out-of-bounds kernel write whose offset and data are attacker-controlled.\nA:H - Corrupting fpdu_part_rcvd/fpdu_part_rem and writing out of bounds from siw_qp crashes or panics the kernel. A remote peer can repeat this on every connection." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/sw/siw/siw_qp_rx.c" ], "versions": [ { "version": "e3917c85f41ef1df64e27dc0e46ab0d803c5e73e", "lessThan": "2c6fbcf4bfac0b2b186acc8d91154c0fa24468a7", "status": "affected", "versionType": "git" }, { "version": "308cd50f174c95a507527037f4de1a0396aa4325", "lessThan": "af9f5b474a260ad23ffb9793d716a5e3bbce3b48", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "262dcd809723723ed8a4e05437ec7e9c21a8f17e", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "eb4d7a946970469b3ab0c762432bf161d5b0836c", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "8628f8ebf41669302513fb3f0bf0eba38b226742", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "b72dcfb9bf1f0f0147cda03dc59e4002a315067f", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "e6bdfdf3bcb02d0d626a45e8c98b7e63d2fddf9d", "status": "affected", "versionType": "git" }, { "version": "754209850df8367c954ac1de7671c7430b1f342c", "lessThan": "9ff797e516dbc1ecb73701ec4c24055712d44411", "status": "affected", "versionType": "git" }, { "version": "e09caa38e10bcf027100cc22b0e3cc745a39ef0a", "status": "affected", "versionType": "git" }, { "version": "0c14f795a9eab9344230f9933798b8ee496f497d", "status": "affected", "versionType": "git" }, { "version": "7fada7c6962219b6fc4ff4e62e46a936af110dd9", "status": "affected", "versionType": "git" }, { "version": "5.10.150", "lessThan": "5.10.271", "status": "affected", "versionType": "semver" }, { "version": "5.15.75", "lessThan": "5.15.222", "status": "affected", "versionType": "semver" }, { "version": "5.4.220", "lessThan": "5.5", "status": "affected", "versionType": "semver" }, { "version": "5.19.17", "lessThan": "5.20", "status": "affected", "versionType": "semver" }, { "version": "6.0.3", "lessThan": "6.1", "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/infiniband/sw/siw/siw_qp_rx.c" ], "versions": [ { "version": "6.1", "status": "affected" }, { "version": "0", "lessThan": "6.1", "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": "5.10.150", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.75", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.18.54" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "7.2.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "7.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4.220" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19.17" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/2c6fbcf4bfac0b2b186acc8d91154c0fa24468a7" }, { "url": "https://git.kernel.org/stable/c/af9f5b474a260ad23ffb9793d716a5e3bbce3b48" }, { "url": "https://git.kernel.org/stable/c/262dcd809723723ed8a4e05437ec7e9c21a8f17e" }, { "url": "https://git.kernel.org/stable/c/eb4d7a946970469b3ab0c762432bf161d5b0836c" }, { "url": "https://git.kernel.org/stable/c/8628f8ebf41669302513fb3f0bf0eba38b226742" }, { "url": "https://git.kernel.org/stable/c/b72dcfb9bf1f0f0147cda03dc59e4002a315067f" }, { "url": "https://git.kernel.org/stable/c/e6bdfdf3bcb02d0d626a45e8c98b7e63d2fddf9d" }, { "url": "https://git.kernel.org/stable/c/9ff797e516dbc1ecb73701ec4c24055712d44411" } ], "title": "RDMA/siw: Bound fragmented header copies by the remaining length", "x_generator": { "engine": "bippy-1.2.0" } } } }