{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2024-44973",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-09-10T17:39:02.040290Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-09-12T17:33:34.160Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "mm/slub.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b35cd7f1e969aaa63e6716d82480f6b8a3230949",
              "status": "affected",
              "version": "782f8906f8057efc7151b4b98b0a0280a71d005f",
              "versionType": "git"
            },
            {
              "lessThan": "a371d558e6f3aed977a8a7346350557de5d25190",
              "status": "affected",
              "version": "782f8906f8057efc7151b4b98b0a0280a71d005f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "mm/slub.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.10.*",
              "status": "unaffected",
              "version": "6.10.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.11",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.10.5",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.11",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm, slub: do not call do_slab_free for kfence object\n\nIn 782f8906f805 the freeing of kfence objects was moved from deep\ninside do_slab_free to the wrapper functions outside. This is a nice\nchange, but unfortunately it missed one spot in __kmem_cache_free_bulk.\n\nThis results in a crash like this:\n\nBUG skbuff_head_cache (Tainted: G S  B       E     ): Padding overwritten. 0xffff88907fea0f00-0xffff88907fea0fff @offset=3840\n\nslab_err (mm/slub.c:1129)\nfree_to_partial_list (mm/slub.c:? mm/slub.c:4036)\nslab_pad_check (mm/slub.c:864 mm/slub.c:1290)\ncheck_slab (mm/slub.c:?)\nfree_to_partial_list (mm/slub.c:3171 mm/slub.c:4036)\nkmem_cache_alloc_bulk (mm/slub.c:? mm/slub.c:4495 mm/slub.c:4586 mm/slub.c:4635)\nnapi_build_skb (net/core/skbuff.c:348 net/core/skbuff.c:527 net/core/skbuff.c:549)\n\nAll the other callers to do_slab_free appear to be ok.\n\nAdd a kfence_free check in __kmem_cache_free_bulk to avoid the crash."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The primary and reported trigger is the NIC receive softirq path \u2014 `napi_build_skb()` \u2192 `napi_skb_cache_get()` \u2192 `kmem_cache_alloc_bulk(skbuff_cache, GFP_ATOMIC, \u2026)` \u2014 driven entirely by inbound packets, with the same remote traffic flood supplying the GFP_ATOMIC pressure that makes the bulk allocation fail mid-array. No local access is needed to reach the vulnerable free path.\nAC:H - Exploitation requires KFENCE to be active with a non-zero sample interval, the timer-driven `kfence_allocation_gate` (~10 allocations/second system-wide) to land on one of the attacker\u0027s bulk-allocation slots, and that same bulk allocation to then fail at a later index \u2014 the KFENCE sampling gate is a periodic timer the attacker cannot influence, so the required coincidence is beyond attacker control.\nPR:N - The network receive path is reached by any packet arriving on a NIC using `napi_build_skb()`/`napi_alloc_skb()`, with no authentication, credentials, or local account required.\nUI:N - The bulk skb allocation path runs autonomously in softirq context on packet receipt; no victim action of any kind is needed.\nS:U - The corruption is confined to the kernel\u0027s own slab allocator metadata and heap; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - A KFENCE pool page is inserted into a live cache\u0027s partial list, so SLUB subsequently hands out memory aliasing other subsystems\u0027 live KFENCE-guarded objects, and free hooks read `obj_exts[]` out of bounds into static kernel data \u2014 both allow disclosure of arbitrary kernel memory contents.\nI:H - `set_freepointer()` writes past the KFENCE object into the redzone/guard page, `slab-\u003einuse` underflows to 65535, and the aliased pool page lets the allocator return the same memory to two owners, plus out-of-bounds `obj_exts[]` writes into `kfence_metadata_init[]` \u2014 a full heap corruption primitive suitable for control-flow hijacking.\nA:H - The reported real-world effect is a slab corruption BUG (`Padding overwritten` / `check_slab`) and kernel crash; without debug enabled, allocations served from unmapped KFENCE guard pages and the NULL `slab_cache` on the injected page cause oopses and panics."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:37:23.425Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b35cd7f1e969aaa63e6716d82480f6b8a3230949"
        },
        {
          "url": "https://git.kernel.org/stable/c/a371d558e6f3aed977a8a7346350557de5d25190"
        }
      ],
      "title": "mm, slub: do not call do_slab_free for kfence object",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2024-44973",
    "datePublished": "2024-09-04T19:00:23.444Z",
    "dateReserved": "2024-08-21T05:34:56.669Z",
    "dateUpdated": "2026-08-05T11:37:23.425Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}