{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64582", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.798Z", "datePublished": "2026-08-05T11:25:29.082Z", "dateUpdated": "2026-08-19T16:29:09.006Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:29:09.006Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/rxe: Fix a use-after-free problem in rxe_mmap\n\nrxe_mmap() removes a rxe_mmap_info struct from the pending_mmaps list\nand releases pending_lock while the struct's kref is still at 1:\n\n list_del_init(&ip->pending_mmaps);\n spin_unlock_bh(&rxe->pending_lock); /* ref == 1, no lock held */\n ret = remap_vmalloc_range(vma, ip->obj, 0); /* walks PTEs */\n [...]\n rxe_vma_open(vma); /* kref_get, ref → 2 */\n remap_vmalloc_range_partial() walks PTEs without any lock.\n\nA concurrent DESTROY_CQ ioctl on another CPU calls:\n\n kref_put(&q->ip->ref, rxe_mmap_release) /* ref 1→0 */\n vfree(ip->obj) /* clears vmalloc PTEs mid-walk */\n kfree(ip) /* frees rxe_mmap_info */\n\nThis yields:\n\n 1. Kernel crash, vmalloc_to_page() returns NULL when vfree wins the\n per-PTE race -> vm_insert_page(NULL) → GPF in validate_page_before_insert\n\n 2. Page UAF, vmalloc_to_page() reads a stale PTE before vfree clears\n it. User VMA holds a PTE to a free'd page which might eventually get\n reallocated later by vmalloc which allows the attacker to get a clean\n page-level UAF.\n\n It is worth noting that even though a page-level UAF is possible given\n the strong primitive, it is statistically very difficult to achieve\n given the very short time window (after the last insert_page and before\n the kref_get).\n\nThe call trace are as below:\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]\n CPU: 0 UID: 1000 PID: 413 Comm: poc Not tainted 7.0.0-rc5-dirty #28 PREEMPT(lazy)\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014\n RIP: 0010:validate_page_before_insert+0x32/0x300\n Code: e5 41 57 41 56 49 89 fe 41 55 41 54 53 48 89 f3 e8 93 b5 a3 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 7b 02 00 00 4c 8b 63 08 31 ff 4d 89 e5 41 83 e5\n RSP: 0018:ffff88811b15f2f0 EFLAGS: 00000202\n RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000\n RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000008\n RBP: ffff88811b15f318 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881181eee00\n R13: 0000000000000000 R14: ffff8881181eee00 R15: ffff8881181eee20\n FS: 00007b1e000f76c0(0000) GS:ffff8884268e0000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007b1e00a24ac0 CR3: 0000000116eb3000 CR4: 00000000000006f0\n Call Trace:\n \n insert_page+0x8f/0x190\n ? __pfx_insert_page+0x10/0x10\n ? kasan_save_alloc_info+0x38/0x60\n vm_insert_page+0x2e7/0x400\n remap_vmalloc_range_partial+0x212/0x3e0\n remap_vmalloc_range+0x6e/0xb0\n ? __kasan_check_write+0x14/0x30\n rxe_mmap+0x2e9/0x5d0\n ib_uverbs_mmap+0x1ad/0x2c0\n __mmap_region+0x12c2/0x2ad0\n ? __pfx___mmap_region+0x10/0x10\n ? __sanitizer_cov_trace_switch+0x58/0xb0\n ? mas_prev_slot+0x360/0x39c0\n ? __sanitizer_cov_trace_switch+0x58/0xb0\n ? mas_next_slot+0x1e5b/0x2f40\n ? __sanitizer_cov_trace_cmp8+0x18/0x30\n ? unmapped_area_topdown+0x4dd/0x610\n ? kfree+0x1b1/0x440\n ? free_cpumask_var+0x16/0x30\n ? __kasan_slab_free+0x7d/0xa0\n ? __sanitizer_cov_trace_cmp8+0x18/0x30\n mmap_region+0x2e6/0x3c0\n do_mmap+0xa3e/0x12a0\n ? __pfx_do_mmap+0x10/0x10\n ? __kasan_check_write+0x14/0x30\n ? down_write_killable+0xba/0x160\n ? __pfx_down_write_killable+0x10/0x10\n ? __sanitizer_cov_trace_cmp4+0x16/0x30\n vm_mmap_pgoff+0x2d4/0x4a0\n ? __pfx_vm_mmap_pgoff+0x10/0x10\n ? fget+0x1bf/0x270\n ksys_mmap_pgoff+0x40c/0x690\n ? __sanitizer_cov_trace_const_cmp4+0x16/0x30\n ? __pfx_ksys_mmap_pgoff+0x10/0x10\n ? __kasan_check_write+0x14/0x30\n ? _raw_spin_trylock+0xbb/0x130\n ? __pfx__raw_spin_trylock+0x10/0x10\n __x64_sys_mmap+0x135/0x1e0\n x64_sys_c\n---truncated---" } ], "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 - Triggered via local mmap on /dev/infiniband/uverbsN (ib_uverbs_mmap→rxe_mmap) racing DESTROY_CQ/QP/SRQ ioctls; not reachable from RoCE/UDP packet processing.\nAC:L - Attacker controls both sides—mmap of the pending CQ/QP/SRQ queue buffer and concurrent destroy that kref_puts to rxe_mmap_release—and can retry unboundedly; PoC shows reliable crash.\nPR:L - uverbs_devnode() publishes /dev/infiniband/uverbs* as 0666 with no capability checks on create/mmap/destroy; once Soft-RoCE exists (admin setup), any unprivileged user (PoC UID 1000) can exploit.\nUI:N - Attacker opens uverbs, creates a CQ/QP/SRQ, then races mmap with destroy from its own threads; no victim action required.\nS:U - UAF corrupts kernel heap/vmalloc within the host kernel authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Race frees rxe_mmap_info and vfree's the queue while remap_vmalloc_range still walks it; stale PTEs can leave a user VMA mapped to reallocated pages, enabling page-level UAF reads.\nI:H - Same page-level UAF / freed-object control yields write primitives via remapped freed pages and heap reuse, sufficient for control-flow hijacking per UAF guidance.\nA:H - Concurrent vfree during PTE walk returns NULL to vm_insert_page, causing the documented GPF/oops in validate_page_before_insert; crash is reliably repeatable." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/sw/rxe/rxe_mmap.c" ], "versions": [ { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "b810352d0916796dabe633cdb9adee9863ab4911", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "aef5ea8578f97f2701039600846a8bcf5f21e863", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "3371f2036e0f970166bbb624e25bba46d32fa18e", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "665fb7d22a700c66a78db0cf88c6e6a649aba9d0", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "e038d42cc09ca1da9d3568ce8ae062b2bfb3bc0e", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "e59a6aa89e0fcd1d0707832eb4654fd9ae7d31e6", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "3525987a392536f31a484833af258971af63b24c", "status": "affected", "versionType": "git" }, { "version": "8700e3e7c4857d28ebaa824509934556da0b3e76", "lessThan": "35744ab3d03c5fca8c1752f53fc8fc674e14c561", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/infiniband/sw/rxe/rxe_mmap.c" ], "versions": [ { "version": "4.8", "status": "affected" }, { "version": "0", "lessThan": "4.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "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:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b810352d0916796dabe633cdb9adee9863ab4911" }, { "url": "https://git.kernel.org/stable/c/aef5ea8578f97f2701039600846a8bcf5f21e863" }, { "url": "https://git.kernel.org/stable/c/3371f2036e0f970166bbb624e25bba46d32fa18e" }, { "url": "https://git.kernel.org/stable/c/665fb7d22a700c66a78db0cf88c6e6a649aba9d0" }, { "url": "https://git.kernel.org/stable/c/e038d42cc09ca1da9d3568ce8ae062b2bfb3bc0e" }, { "url": "https://git.kernel.org/stable/c/e59a6aa89e0fcd1d0707832eb4654fd9ae7d31e6" }, { "url": "https://git.kernel.org/stable/c/3525987a392536f31a484833af258971af63b24c" }, { "url": "https://git.kernel.org/stable/c/35744ab3d03c5fca8c1752f53fc8fc674e14c561" } ], "title": "RDMA/rxe: Fix a use-after-free problem in rxe_mmap", "x_generator": { "engine": "bippy-1.2.0" } } } }