{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-97421", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-24T14:53:16.868Z", "datePublished": "2026-09-24T16:03:31.505Z", "dateUpdated": "2026-09-25T05:10:30.134Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-25T05:10:30.134Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()\n\nSeveral corner cases, especially important on 32 bits:\n\n- umem->iova is u64, the function argument should pass in u64 or\n iova will be truncated\n- Check that the length is not too large for the iova\n- Check that lengths > 4G don't overflow the GENMASK"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - Attacker-controlled cmd.hca_va and cmd.length reach ib_umem_find_best_pgsz() via open of /dev/infiniband/uverbsX, then ib_uverbs_write(IB_USER_VERBS_CMD_REG_MR)/ib_uverbs_reg_mr() or UVERBS_METHOD_REG_MR ioctl, then pd->ops.reg_user_mr() (mlx5_ib_reg_user_mr/irdma_reg_user_mr/efa_register_mr). Remote RDMA packets do not supply virt or umem->length.\nAC:L - ib_uverbs_reg_mr() only requires (start & ~PAGE_MASK)==(hca_va & ~PAGE_MASK), so the attacker picks hca_va near 2^63 or U64_MAX with a small pinned region and makes (umem->length-1+virt) overflow or bits_per() return BITS_PER_LONG, hitting the unguarded GENMASK() deterministically with no race.\nPR:L - uverbs_devnode() creates /dev/infiniband/uverbs* mode 0666 and ib_uverbs_open() has no capability check (only rdma_dev_access_netns). ib_umem_get_va() needs can_do_mlock() (RLIMIT_MEMLOCK!=0) and ib_check_mr_access(); CAP_SYS_ADMIN/CAP_IPC_LOCK are not required.\nUI:N - After opening uverbs the attacker allocates a PD and issues IB_USER_VERBS_CMD_REG_MR or UVERBS_METHOD_REG_MR with their own start, length, and hca_va; no victim mount or other user action is required.\nS:U - A wrong page size or truncated umem->iova from ib_umem_find_best_pgsz() misprograms that host's RDMA MTT/PBL. This stays in the kernel/device memory-management authority and is not a KVM/Xen guest-to-host escape or IOMMU VM-boundary bypass.\nC:H - When bits_per((umem->length-1+virt)^virt)>=BITS_PER_LONG, GENMASK(BITS_PER_LONG-1, bits) is invalid and mask can be 0, so the function returns rounddown_pow_of_two(pgsz_bitmap) (largest HW page). mlx5_ib_populate_pas()/rdma_umem_for_each_dma_block() then install oversized MTT/PBL entries, so the NIC DMA-reads physical memory beyond the pinned umem.\nI:H - The same oversized page size is programmed into hardware (efa_register_mr params.page_shift, ionic_pgtbl_init, mlx5 mkey PAS). With IB_ACCESS_LOCAL_WRITE or IB_ACCESS_REMOTE_WRITE from the REG_MR access_flags, the device DMA-writes outside the registered region, which is an arbitrary physical write.\nA:H - GENMASK() with l>h is a shift UB that can oops (UBSAN) or yield mask==0; mis-sized pages cause IOMMU/device faults. ib_umem_is_contiguous() (mlx5_ib_db_map_user_desc, efa create_cq) can also treat a non-contiguous umem as one DMA block and fault the kernel or NIC."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/infiniband/core/umem.c", "include/rdma/ib_umem.h"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "ae3cf7d2c4d506c5c91746321644e1a08d989e2a", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "5fc5b73109540809b094710fac44da81dd8a3ff8", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "09ea6837a0434fb4db99528a5055b6d822135dcf", "status": "affected", "versionType": "git"}, {"version": "0", "lessThan": "6.12.111", "status": "affected", "versionType": "semver"}, {"version": "0", "lessThan": "6.18.53", "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/core/umem.c", "include/rdma/ib_umem.h"], "versions": [{"version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.111"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.53"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/ae3cf7d2c4d506c5c91746321644e1a08d989e2a"}, {"url": "https://git.kernel.org/stable/c/5fc5b73109540809b094710fac44da81dd8a3ff8"}, {"url": "https://git.kernel.org/stable/c/09ea6837a0434fb4db99528a5055b6d822135dcf"}], "title": "RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/infiniband/core/umem.c", "include/rdma/ib_umem.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "ae3cf7d2c4d506c5c91746321644e1a08d989e2a", "status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "versionType": "git"}, {"lessThan": "5fc5b73109540809b094710fac44da81dd8a3ff8", "status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "versionType": "git"}, {"lessThan": "09ea6837a0434fb4db99528a5055b6d822135dcf", "status": "affected", "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "versionType": "git"}, {"lessThan": "6.12.111", "status": "affected", "version": "0", "versionType": "semver"}, {"lessThan": "6.18.53", "status": "affected", "version": "0", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/infiniband/core/umem.c", "include/rdma/ib_umem.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.111", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.53", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()\n\nSeveral corner cases, especially important on 32 bits:\n\n- umem->iova is u64, the function argument should pass in u64 or\n iova will be truncated\n- Check that the length is not too large for the iova\n- Check that lengths > 4G don't overflow the GENMASK"}], "id": "CVE-2026-97421", "lastModified": "2026-09-25T05:17:04.973", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-24T17:17:19.993", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/09ea6837a0434fb4db99528a5055b6d822135dcf"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5fc5b73109540809b094710fac44da81dd8a3ff8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ae3cf7d2c4d506c5c91746321644e1a08d989e2a"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,ae3cf7d2c4d506c5c91746321644e1a08d989e2a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,5fc5b73109540809b094710fac44da81dd8a3ff8)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,09ea6837a0434fb4db99528a5055b6d822135dcf)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.12.111)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.18.53)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.111,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.53,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-24T23:00:14.430226+00:00", "updated": "2026-09-25T03:00:09.028878+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-20", "CWE-190"]}