{"id":"CVE-2026-68419","state":"PUBLISHED","title":"RDMA/irdma: Prevent rereg_mr for non-mem regions","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/irdma: Prevent rereg_mr for non-mem regions\n\nWhen a QP/CQ/SRQ is created, a two step process is used\nwhere the buffer is allocated in userspace and explicitly\nregistered with the normal reg_mr mechanism prior to creating\nthe actual QP/CQ/SRQ object.\n\nThese special registrations are indicated via an ABI field\nso the driver knows that they do not have a valid mkey and\nto skip the actual CQP command submission.\n\nSince these are real MR objects from the core's perspective,\nit is possible for a user application to invoke rereg_mr on them\nand cause a real CQP op to be emitted with the zero-initialized\nmkey value of 0.\n\nFix this by preventing rereg_mr on these special regions.","publishedAt":"2026-08-10T12:04:39.912Z","updatedAt":"2026-10-19T21:09:09.507Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"715fdb3b30541cc8180b7cdc6aa9f8c307afdf25","status":"affected","lessThan":"fb46d134e1b8690bed2da9005b36d32d2efd34ac","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"b5029e91c63406e4f4c8d58161048b41b6f0bd8c","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"ca1c29f05274b737dc964e28b97803750d7cf7ec","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"dbaa37e060918c45517786e37ecab0f300b48fa9","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"a846aecb931b4d65d5eafa92a0623545af46d4f2","versionType":"git"},{"version":"6.6.120","status":"affected","lessThan":"6.6.148","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/irdma/verbs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.7","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","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/irdma/verbs.c"]}],"references":["https://git.kernel.org/stable/c/fb46d134e1b8690bed2da9005b36d32d2efd34ac","https://git.kernel.org/stable/c/b5029e91c63406e4f4c8d58161048b41b6f0bd8c","https://git.kernel.org/stable/c/ca1c29f05274b737dc964e28b97803750d7cf7ec","https://git.kernel.org/stable/c/dbaa37e060918c45517786e37ecab0f300b48fa9","https://git.kernel.org/stable/c/a846aecb931b4d65d5eafa92a0623545af46d4f2"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/68xxx/CVE-2026-68419.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68419","state":"PUBLISHED","datePublished":"2026-08-10T12:04:39.912Z","dateUpdated":"2026-10-19T21:09:09.507Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-30T09:28:09.391Z"},"containers":{"cna":{"title":"RDMA/irdma: Prevent rereg_mr for non-mem regions","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/irdma: Prevent rereg_mr for non-mem regions\n\nWhen a QP/CQ/SRQ is created, a two step process is used\nwhere the buffer is allocated in userspace and explicitly\nregistered with the normal reg_mr mechanism prior to creating\nthe actual QP/CQ/SRQ object.\n\nThese special registrations are indicated via an ABI field\nso the driver knows that they do not have a valid mkey and\nto skip the actual CQP command submission.\n\nSince these are real MR objects from the core's perspective,\nit is possible for a user application to invoke rereg_mr on them\nand cause a real CQP op to be emitted with the zero-initialized\nmkey value of 0.\n\nFix this by preventing rereg_mr on these special regions."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"715fdb3b30541cc8180b7cdc6aa9f8c307afdf25","status":"affected","lessThan":"fb46d134e1b8690bed2da9005b36d32d2efd34ac","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"b5029e91c63406e4f4c8d58161048b41b6f0bd8c","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"ca1c29f05274b737dc964e28b97803750d7cf7ec","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"dbaa37e060918c45517786e37ecab0f300b48fa9","versionType":"git"},{"version":"5ac388db27c443dadfbb0b8b23fa7ccf429d901a","status":"affected","lessThan":"a846aecb931b4d65d5eafa92a0623545af46d4f2","versionType":"git"},{"version":"6.6.120","status":"affected","lessThan":"6.6.148","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/hw/irdma/verbs.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.7","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.6","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/irdma/verbs.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/fb46d134e1b8690bed2da9005b36d32d2efd34ac"},{"url":"https://git.kernel.org/stable/c/b5029e91c63406e4f4c8d58161048b41b6f0bd8c"},{"url":"https://git.kernel.org/stable/c/ca1c29f05274b737dc964e28b97803750d7cf7ec"},{"url":"https://git.kernel.org/stable/c/dbaa37e060918c45517786e37ecab0f300b48fa9"},{"url":"https://git.kernel.org/stable/c/a846aecb931b4d65d5eafa92a0623545af46d4f2"}],"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 - The vulnerability is reached through the ib_uverbs REREG_MR command on /dev/infiniband/uverbs*, a local character device; no network input reaches irdma_rereg_user_mr(). The resulting corrupt hardware STAG can later be abused over RDMA, but initial access is local.\nAC:L - The attacker fully controls every precondition: register a buffer with reg_type IRDMA_MEMREG_TYPE_QP/CQ/SRQ, then call rereg_mr on that handle. There is no race, no timing dependency and no reliance on memory layout the attacker cannot influence.\nPR:L - Only an open file descriptor on /dev/infiniband/uverbsN is needed; rdma-core udev rules ship these nodes world-accessible (0666) and they are routinely exposed to containers. ib_uverbs_rereg_mr() performs no capability check, only uobject ownership of the caller's own MR.\nUI:N - The attacker performs the entire sequence (reg_mr with a non-MEM reg_type, then rereg_mr) from its own process. No action by any other user or administrator is required.\nS:U - The corruption stays within the kernel/RDMA-device security authority managed by the same OS instance; there is no VM, IOMMU or hypervisor boundary crossed by the erroneous CQP command.\nC:H - Programming HW STAG index 0 with attacker-chosen remote-read rights, combined with dereg_mr never invalidating it, leaves a live hardware mapping over PBLEs and umem pages that are freed and reused, giving RDMA-read access to recycled kernel/other-process memory; it can also collide with another process's MR at stag index 0.\nI:H - The same stale/hijacked STAG can carry IB_ACCESS_REMOTE_WRITE, and the IB_MR_REREG_TRANS path frees the PBLEs and releases the umem of a live QP/CQ/SRQ while hardware keeps DMAing into those pages, yielding device-driven writes into freed and reallocated kernel memory.\nA:H - Issuing a CQP op with a zero mkey corrupts device state and can fail the CQP op, triggering the driver's reset path; the DMA-after-free into recycled pages and the clobbering of another region's STAG readily produce kernel memory corruption, oops or full RDMA device reset."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:05:14.336Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.120","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-68419","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:48:37.991046Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","type":"CWE","description":"CWE-20 Improper Input Validation"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T21:09:09.507Z"}}]}}}