FKIE_CVE-2026-64582

Vulnerability from fkie_nvd - Published: 2026-08-05 12:18 - Updated: 2026-08-08 15:16
Severity
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix a use-after-free problem in rxe_mmap rxe_mmap() removes a rxe_mmap_info struct from the pending_mmaps list and releases pending_lock while the struct's kref is still at 1: list_del_init(&ip->pending_mmaps); spin_unlock_bh(&rxe->pending_lock); /* ref == 1, no lock held */ ret = remap_vmalloc_range(vma, ip->obj, 0); /* walks PTEs */ [...] rxe_vma_open(vma); /* kref_get, ref → 2 */ remap_vmalloc_range_partial() walks PTEs without any lock. A concurrent DESTROY_CQ ioctl on another CPU calls: kref_put(&q->ip->ref, rxe_mmap_release) /* ref 1→0 */ vfree(ip->obj) /* clears vmalloc PTEs mid-walk */ kfree(ip) /* frees rxe_mmap_info */ This yields: 1. Kernel crash, vmalloc_to_page() returns NULL when vfree wins the per-PTE race -> vm_insert_page(NULL) → GPF in validate_page_before_insert 2. Page UAF, vmalloc_to_page() reads a stale PTE before vfree clears it. User VMA holds a PTE to a free'd page which might eventually get reallocated later by vmalloc which allows the attacker to get a clean page-level UAF. It is worth noting that even though a page-level UAF is possible given the strong primitive, it is statistically very difficult to achieve given the very short time window (after the last insert_page and before the kref_get). The call trace are as below: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 UID: 1000 PID: 413 Comm: poc Not tainted 7.0.0-rc5-dirty #28 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:validate_page_before_insert+0x32/0x300 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 RSP: 0018:ffff88811b15f2f0 EFLAGS: 00000202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000008 RBP: ffff88811b15f318 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881181eee00 R13: 0000000000000000 R14: ffff8881181eee00 R15: ffff8881181eee20 FS: 00007b1e000f76c0(0000) GS:ffff8884268e0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007b1e00a24ac0 CR3: 0000000116eb3000 CR4: 00000000000006f0 Call Trace: <TASK> insert_page+0x8f/0x190 ? __pfx_insert_page+0x10/0x10 ? kasan_save_alloc_info+0x38/0x60 vm_insert_page+0x2e7/0x400 remap_vmalloc_range_partial+0x212/0x3e0 remap_vmalloc_range+0x6e/0xb0 ? __kasan_check_write+0x14/0x30 rxe_mmap+0x2e9/0x5d0 ib_uverbs_mmap+0x1ad/0x2c0 __mmap_region+0x12c2/0x2ad0 ? __pfx___mmap_region+0x10/0x10 ? __sanitizer_cov_trace_switch+0x58/0xb0 ? mas_prev_slot+0x360/0x39c0 ? __sanitizer_cov_trace_switch+0x58/0xb0 ? mas_next_slot+0x1e5b/0x2f40 ? __sanitizer_cov_trace_cmp8+0x18/0x30 ? unmapped_area_topdown+0x4dd/0x610 ? kfree+0x1b1/0x440 ? free_cpumask_var+0x16/0x30 ? __kasan_slab_free+0x7d/0xa0 ? __sanitizer_cov_trace_cmp8+0x18/0x30 mmap_region+0x2e6/0x3c0 do_mmap+0xa3e/0x12a0 ? __pfx_do_mmap+0x10/0x10 ? __kasan_check_write+0x14/0x30 ? down_write_killable+0xba/0x160 ? __pfx_down_write_killable+0x10/0x10 ? __sanitizer_cov_trace_cmp4+0x16/0x30 vm_mmap_pgoff+0x2d4/0x4a0 ? __pfx_vm_mmap_pgoff+0x10/0x10 ? fget+0x1bf/0x270 ksys_mmap_pgoff+0x40c/0x690 ? __sanitizer_cov_trace_const_cmp4+0x16/0x30 ? __pfx_ksys_mmap_pgoff+0x10/0x10 ? __kasan_check_write+0x14/0x30 ? _raw_spin_trylock+0xbb/0x130 ? __pfx__raw_spin_trylock+0x10/0x10 __x64_sys_mmap+0x135/0x1e0 x64_sys_c ---truncated---
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3525987a392536f31a484833af258971af63b24c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/35744ab3d03c5fca8c1752f53fc8fc674e14c561
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/665fb7d22a700c66a78db0cf88c6e6a649aba9d0
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e038d42cc09ca1da9d3568ce8ae062b2bfb3bc0e
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e59a6aa89e0fcd1d0707832eb4654fd9ae7d31e6
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/infiniband/sw/rxe/rxe_mmap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "665fb7d22a700c66a78db0cf88c6e6a649aba9d0",
              "status": "affected",
              "version": "8700e3e7c4857d28ebaa824509934556da0b3e76",
              "versionType": "git"
            },
            {
              "lessThan": "e038d42cc09ca1da9d3568ce8ae062b2bfb3bc0e",
              "status": "affected",
              "version": "8700e3e7c4857d28ebaa824509934556da0b3e76",
              "versionType": "git"
            },
            {
              "lessThan": "e59a6aa89e0fcd1d0707832eb4654fd9ae7d31e6",
              "status": "affected",
              "version": "8700e3e7c4857d28ebaa824509934556da0b3e76",
              "versionType": "git"
            },
            {
              "lessThan": "3525987a392536f31a484833af258971af63b24c",
              "status": "affected",
              "version": "8700e3e7c4857d28ebaa824509934556da0b3e76",
              "versionType": "git"
            },
            {
              "lessThan": "35744ab3d03c5fca8c1752f53fc8fc674e14c561",
              "status": "affected",
              "version": "8700e3e7c4857d28ebaa824509934556da0b3e76",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/infiniband/sw/rxe/rxe_mmap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.8"
            },
            {
              "lessThan": "4.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc1",
              "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/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\u0027s kref is still at 1:\n\n   list_del_init(\u0026ip-\u003epending_mmaps);\n   spin_unlock_bh(\u0026rxe-\u003epending_lock);   /* ref == 1, no lock held */\n   ret = remap_vmalloc_range(vma, ip-\u003eobj, 0);  /* walks PTEs */\n   [...]\n   rxe_vma_open(vma);                    /* kref_get, ref \u2192 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(\u0026q-\u003eip-\u003eref, rxe_mmap_release)   /* ref 1\u21920 */\n    vfree(ip-\u003eobj)   /* 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 -\u003e vm_insert_page(NULL) \u2192 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\u0027d 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 \u003c80\u003e 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   \u003cTASK\u003e\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---"
    }
  ],
  "id": "CVE-2026-64582",
  "lastModified": "2026-08-08T15:16:33.247",
  "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": "2026-08-05T12:18:57.440",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3525987a392536f31a484833af258971af63b24c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/35744ab3d03c5fca8c1752f53fc8fc674e14c561"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/665fb7d22a700c66a78db0cf88c6e6a649aba9d0"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e038d42cc09ca1da9d3568ce8ae062b2bfb3bc0e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e59a6aa89e0fcd1d0707832eb4654fd9ae7d31e6"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.