{"id":"CVE-2026-74396","state":"PUBLISHED","title":"RDMA/mlx5: Fix UMR XLT cleanup on ODP populate failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Fix UMR XLT cleanup on ODP populate failure\n\nmlx5r_umr_update_xlt() allocates and DMA maps an XLT buffer with\nmlx5r_umr_create_xlt(). The buffer is released by the common cleanup path\nthrough mlx5r_umr_unmap_free_xlt().\n\nAfter mlx5_odp_populate_xlt() became fallible, its error path returned\ndirectly and skipped that cleanup. This leaks the XLT DMA mapping and\nbuffer. If the emergency XLT page was used, it also leaves\nxlt_emergency_page_mutex locked.\n\nBreak out of the loop so execution falls through the existing cleanup path.","publishedAt":"2026-08-15T05:59:08.694Z","updatedAt":"2026-10-16T19:05:41.026Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"ffa85a2c197935ace6f1634ad9eb0a44bc615670","versionType":"git"},{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"9619909d4869afe720904c6888a289b9ac3055b8","versionType":"git"},{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"1eae35b37923cb71b0cb5136d00671440d488b9f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/mlx5/umr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/mlx5/umr.c"]}],"references":["https://git.kernel.org/stable/c/ffa85a2c197935ace6f1634ad9eb0a44bc615670","https://git.kernel.org/stable/c/9619909d4869afe720904c6888a289b9ac3055b8","https://git.kernel.org/stable/c/1eae35b37923cb71b0cb5136d00671440d488b9f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74396.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74396","state":"PUBLISHED","datePublished":"2026-08-15T05:59:08.694Z","dateUpdated":"2026-10-16T19:05:41.026Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.891Z"},"containers":{"cna":{"title":"RDMA/mlx5: Fix UMR XLT cleanup on ODP populate failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Fix UMR XLT cleanup on ODP populate failure\n\nmlx5r_umr_update_xlt() allocates and DMA maps an XLT buffer with\nmlx5r_umr_create_xlt(). The buffer is released by the common cleanup path\nthrough mlx5r_umr_unmap_free_xlt().\n\nAfter mlx5_odp_populate_xlt() became fallible, its error path returned\ndirectly and skipped that cleanup. This leaks the XLT DMA mapping and\nbuffer. If the emergency XLT page was used, it also leaves\nxlt_emergency_page_mutex locked.\n\nBreak out of the loop so execution falls through the existing cleanup path."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"ffa85a2c197935ace6f1634ad9eb0a44bc615670","versionType":"git"},{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"9619909d4869afe720904c6888a289b9ac3055b8","versionType":"git"},{"version":"1efe8c0670d6a6883faa09c9abc746c741f5664a","status":"affected","lessThan":"1eae35b37923cb71b0cb5136d00671440d488b9f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/mlx5/umr.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/mlx5/umr.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ffa85a2c197935ace6f1634ad9eb0a44bc615670"},{"url":"https://git.kernel.org/stable/c/9619909d4869afe720904c6888a289b9ac3055b8"},{"url":"https://git.kernel.org/stable/c/1eae35b37923cb71b0cb5136d00671440d488b9f"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - Remote RDMA peers trigger mlx5 ODP hardware page faults over RoCE/InfiniBand (mlx5_ib_mr_rdma_pfault_handler → pagefault_real_mr → mlx5r_umr_update_xlt), reaching the buggy cleanup on mlx5 AI/HPC/cloud servers without local syscalls.\nAC:L - An attacker can repeatedly drive ODP page faults, exhaust memory to force the emergency XLT page path, and retry until mlx5_odp_populate_xlt()/hmm_dma_map_pfn() fails; no uncontrollable race or memory layout is required.\nPR:N - The RDMA responder page-fault path executes in kernel workqueues on packets from a connected remote peer and performs no Linux capability or credential check before calling mlx5r_umr_update_xlt().\nUI:N - Exploitation requires only attacker-generated RDMA traffic against exported ODP memory regions once a queue pair exists; no additional victim action beyond normal RDMA service operation is needed.\nS:U - The DMA mapping leak and permanent xlt_emergency_page_mutex lock affect mlx5 driver resources within the same host kernel security authority; there is no VM escape or IOMMU-boundary bypass.\nC:N - The bug skips unmap/free of an XLT translation buffer; it does not corrupt memory, dereference freed objects, or provide an arbitrary kernel read primitive.\nI:N - No out-of-bounds write, use-after-free, or control-flow corruption occurs; the defect only leaks resources rather than enabling arbitrary data modification.\nA:H - Each failure leaks a DMA mapping and buffer, and on the emergency-page path permanently locks xlt_emergency_page_mutex, deadlocking subsequent UMR XLT updates and disabling ODP/RDMA on the mlx5 device."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:46:40.931Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-74396","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T18:55:21.919337Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T19:05:41.026Z"}}]}}}