{"api_version":"1","generated_at":"2026-08-02T19:43:20+00:00","cve":"CVE-2026-64269","urls":{"html":"https://cve.report/CVE-2026-64269","api":"https://cve.report/api/cve/CVE-2026-64269.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64269","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64269"},"summary":{"title":"RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg\n\nWhen the server answers an RTRS READ, rdma_write_sg() builds the source\nscatter/gather entry for the IB_WR_RDMA_WRITE that returns data to the\npeer. Its length is taken directly from the wire descriptor:\n\n  plist->length = le32_to_cpu(id->rd_msg->desc[0].len);\n\nrd_msg points into the chunk buffer that the remote peer filled via\nRDMA-WRITE-WITH-IMM (rtrs_srv_rdma_done() -> process_io_req() ->\nprocess_read()), so desc[0].len is attacker-controlled and, before this\nchange, was only rejected when zero. The source address is the fixed\nchunk start (dma_addr[msg_id]) and the source lkey is the PD-wide\nlocal_dma_lkey, which is not tied to the chunk's MR mapping, so the verbs\nlayer does not constrain the transfer length to max_chunk_size. msg_id\nand off are bounded against queue_depth and max_chunk_size in\nrtrs_srv_rdma_done(), but desc[0].len is a separate field that was not\nchecked against the chunk size.\n\nA peer that advertises desc[0].len larger than max_chunk_size can make\nthe posted RDMA write read past the chunk's mapped region. The resulting\nbehaviour depends on the IOMMU configuration: with no IOMMU or in\npassthrough mode the read may extend into memory adjacent to the chunk\nand be returned to the peer, which can disclose host memory; with a\ntranslating IOMMU the out-of-range access is expected to fault and abort\nthe connection. In either case the transfer exceeds what the protocol\npermits and is driven by a remote peer.\n\nReject a descriptor length above max_chunk_size, mirroring the existing\noff >= max_chunk_size bound in rtrs_srv_rdma_done(). Legitimate clients\ndo not exceed it: the client sets desc[0].len to its MR length, which is\ncapped at the negotiated max_io_size (max_chunk_size - MAX_HDR_SIZE).","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:07","updated_at":"2026-07-30 15:00:27"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"9.1","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":9.1,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"9.1","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","data":{"baseScore":9.1,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/6cada540150894e81042a0ae0c796a21a9a877da","name":"https://git.kernel.org/stable/c/6cada540150894e81042a0ae0c796a21a9a877da","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2912f3d40355dabc08fdbaaf2764d02445fe88dc","name":"https://git.kernel.org/stable/c/2912f3d40355dabc08fdbaaf2764d02445fe88dc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5a45d0aa1fa50a333ce5763ade744e2d89838667","name":"https://git.kernel.org/stable/c/5a45d0aa1fa50a333ce5763ade744e2d89838667","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/68c09762172f6224e9ddf9b0a60bacbb36e443eb","name":"https://git.kernel.org/stable/c/68c09762172f6224e9ddf9b0a60bacbb36e443eb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6f40246f4312fdbab5a13cc440adebf95eb2aa66","name":"https://git.kernel.org/stable/c/6f40246f4312fdbab5a13cc440adebf95eb2aa66","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/da3e44add94b05dfde56f898421922f5cf35705f","name":"https://git.kernel.org/stable/c/da3e44add94b05dfde56f898421922f5cf35705f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/963af8d97a8c6a117134a8d0db1415e0489200b1","name":"https://git.kernel.org/stable/c/963af8d97a8c6a117134a8d0db1415e0489200b1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64269","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64269","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9cb837480424e78ed585376f944088246685aec3 68c09762172f6224e9ddf9b0a60bacbb36e443eb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9cb837480424e78ed585376f944088246685aec3 6cada540150894e81042a0ae0c796a21a9a877da git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9cb837480424e78ed585376f944088246685aec3 2912f3d40355dabc08fdbaaf2764d02445fe88dc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9cb837480424e78ed585376f944088246685aec3 6f40246f4312fdbab5a13cc440adebf95eb2aa66 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 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semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.96 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64269","cve":"CVE-2026-64269","epss":"0.006790000","percentile":"0.487970000","score_date":"2026-08-01","updated_at":"2026-08-02 00:11:13"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/infiniband/ulp/rtrs/rtrs-srv.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"68c09762172f6224e9ddf9b0a60bacbb36e443eb","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"6cada540150894e81042a0ae0c796a21a9a877da","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"2912f3d40355dabc08fdbaaf2764d02445fe88dc","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"6f40246f4312fdbab5a13cc440adebf95eb2aa66","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"5a45d0aa1fa50a333ce5763ade744e2d89838667","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"da3e44add94b05dfde56f898421922f5cf35705f","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"},{"lessThan":"963af8d97a8c6a117134a8d0db1415e0489200b1","status":"affected","version":"9cb837480424e78ed585376f944088246685aec3","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/infiniband/ulp/rtrs/rtrs-srv.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.8"},{"lessThan":"5.8","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.212","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.178","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.145","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.96","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.39","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.212","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.178","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.145","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.96","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.39","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.4","versionStartIncluding":"5.8","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"5.8","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg\n\nWhen the server answers an RTRS READ, rdma_write_sg() builds the source\nscatter/gather entry for the IB_WR_RDMA_WRITE that returns data to the\npeer. Its length is taken directly from the wire descriptor:\n\n  plist->length = le32_to_cpu(id->rd_msg->desc[0].len);\n\nrd_msg points into the chunk buffer that the remote peer filled via\nRDMA-WRITE-WITH-IMM (rtrs_srv_rdma_done() -> process_io_req() ->\nprocess_read()), so desc[0].len is attacker-controlled and, before this\nchange, was only rejected when zero. The source address is the fixed\nchunk start (dma_addr[msg_id]) and the source lkey is the PD-wide\nlocal_dma_lkey, which is not tied to the chunk's MR mapping, so the verbs\nlayer does not constrain the transfer length to max_chunk_size. msg_id\nand off are bounded against queue_depth and max_chunk_size in\nrtrs_srv_rdma_done(), but desc[0].len is a separate field that was not\nchecked against the chunk size.\n\nA peer that advertises desc[0].len larger than max_chunk_size can make\nthe posted RDMA write read past the chunk's mapped region. The resulting\nbehaviour depends on the IOMMU configuration: with no IOMMU or in\npassthrough mode the read may extend into memory adjacent to the chunk\nand be returned to the peer, which can disclose host memory; with a\ntranslating IOMMU the out-of-range access is expected to fault and abort\nthe connection. In either case the transfer exceeds what the protocol\npermits and is driven by a remote peer.\n\nReject a descriptor length above max_chunk_size, mirroring the existing\noff >= max_chunk_size bound in rtrs_srv_rdma_done(). Legitimate clients\ndo not exceed it: the client sets desc[0].len to its MR length, which is\ncapped at the negotiated max_io_size (max_chunk_size - MAX_HDR_SIZE)."}],"metrics":[{"cvssV3_1":{"baseScore":9.1,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-07-27T04:59:19.367Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/68c09762172f6224e9ddf9b0a60bacbb36e443eb"},{"url":"https://git.kernel.org/stable/c/6cada540150894e81042a0ae0c796a21a9a877da"},{"url":"https://git.kernel.org/stable/c/2912f3d40355dabc08fdbaaf2764d02445fe88dc"},{"url":"https://git.kernel.org/stable/c/6f40246f4312fdbab5a13cc440adebf95eb2aa66"},{"url":"https://git.kernel.org/stable/c/5a45d0aa1fa50a333ce5763ade744e2d89838667"},{"url":"https://git.kernel.org/stable/c/da3e44add94b05dfde56f898421922f5cf35705f"},{"url":"https://git.kernel.org/stable/c/963af8d97a8c6a117134a8d0db1415e0489200b1"}],"title":"RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64269","datePublished":"2026-07-25T08:49:16.946Z","dateReserved":"2026-07-19T15:36:31.775Z","dateUpdated":"2026-07-27T04:59:19.367Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:07","lastModifiedDate":"2026-07-30 15:00:27","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":9.1,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":5.2}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64269","Ordinal":"1","Title":"RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_wri","CVE":"CVE-2026-64269","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64269","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_write_sg\n\nWhen the server answers an RTRS READ, rdma_write_sg() builds the source\nscatter/gather entry for the IB_WR_RDMA_WRITE that returns data to the\npeer. Its length is taken directly from the wire descriptor:\n\n  plist->length = le32_to_cpu(id->rd_msg->desc[0].len);\n\nrd_msg points into the chunk buffer that the remote peer filled via\nRDMA-WRITE-WITH-IMM (rtrs_srv_rdma_done() -> process_io_req() ->\nprocess_read()), so desc[0].len is attacker-controlled and, before this\nchange, was only rejected when zero. The source address is the fixed\nchunk start (dma_addr[msg_id]) and the source lkey is the PD-wide\nlocal_dma_lkey, which is not tied to the chunk's MR mapping, so the verbs\nlayer does not constrain the transfer length to max_chunk_size. msg_id\nand off are bounded against queue_depth and max_chunk_size in\nrtrs_srv_rdma_done(), but desc[0].len is a separate field that was not\nchecked against the chunk size.\n\nA peer that advertises desc[0].len larger than max_chunk_size can make\nthe posted RDMA write read past the chunk's mapped region. The resulting\nbehaviour depends on the IOMMU configuration: with no IOMMU or in\npassthrough mode the read may extend into memory adjacent to the chunk\nand be returned to the peer, which can disclose host memory; with a\ntranslating IOMMU the out-of-range access is expected to fault and abort\nthe connection. In either case the transfer exceeds what the protocol\npermits and is driven by a remote peer.\n\nReject a descriptor length above max_chunk_size, mirroring the existing\noff >= max_chunk_size bound in rtrs_srv_rdma_done(). Legitimate clients\ndo not exceed it: the client sets desc[0].len to its MR length, which is\ncapped at the negotiated max_io_size (max_chunk_size - MAX_HDR_SIZE).","Type":"Description","Title":"RDMA/rtrs-srv: Bound RDMA-Write length to chunk size in rdma_wri"}]}}}