{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/android/dbitmap.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c301ec61ce6f16e21a36b99225ca8a20c1591e10",
              "status": "affected",
              "version": "15d9da3f818cae676f822a04407d3c17b53357d2",
              "versionType": "git"
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            {
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              "status": "affected",
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              "versionType": "git"
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            {
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              "versionType": "git"
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            {
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              "status": "affected",
              "version": "15d9da3f818cae676f822a04407d3c17b53357d2",
              "versionType": "git"
            }
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        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/android/dbitmap.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.11"
            },
            {
              "lessThan": "6.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.52",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.12",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.52",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.12",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.2",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbinder: fix double-free in dbitmap\n\nA process might fail to allocate a new bitmap when trying to expand its\nproc-\u003edmap. In that case, dbitmap_grow() fails and frees the old bitmap\nvia dbitmap_free(). However, the driver calls dbitmap_free() again when\nthe same process terminates, leading to a double-free error:\n\n  ==================================================================\n  BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c\n  Free of addr ffff00000b7c1420 by task kworker/9:1/209\n\n  CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT\n  Hardware name: linux,dummy-virt (DT)\n  Workqueue: events binder_deferred_func\n  Call trace:\n   kfree+0x164/0x31c\n   binder_proc_dec_tmpref+0x2e0/0x55c\n   binder_deferred_func+0xc24/0x1120\n   process_one_work+0x520/0xba4\n  [...]\n\n  Allocated by task 448:\n   __kmalloc_noprof+0x178/0x3c0\n   bitmap_zalloc+0x24/0x30\n   binder_open+0x14c/0xc10\n  [...]\n\n  Freed by task 449:\n   kfree+0x184/0x31c\n   binder_inc_ref_for_node+0xb44/0xe44\n   binder_transaction+0x29b4/0x7fbc\n   binder_thread_write+0x1708/0x442c\n   binder_ioctl+0x1b50/0x2900\n  [...]\n  ==================================================================\n\nFix this issue by marking proc-\u003emap NULL in dbitmap_free()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only through `ioctl()`/`write()` on a binder character device (`/dev/binder` or a binderfs device node), requiring a local process on the system. There is no remote or network-facing path into `binder_transaction()`.\nAC:L - The attacker fully controls both preconditions: the size of the failing `bitmap_zalloc()` (by creating hundreds of thousands of binder references so the doubling bitmap enters costly-order allocations that fail without invoking the OOM killer) and the memory pressure/fragmentation that makes it fail, then chooses exactly when the second free occurs by closing the fd. The window between the two frees is arbitrarily long, making heap grooming reliable.\nPR:L - Binder contains no `capable()` checks at all on this path; on Android every unprivileged app can open a binder device, and on distro kernels with CONFIG_ANDROID_BINDERFS an unprivileged user can mount binderfs inside a user namespace (`FS_USERNS_MOUNT`) and create devices without any capability. Only a basic local account is needed.\nUI:N - The attacking process performs everything itself \u2014 open the device, drive transactions to grow the bitmap, exhaust memory, then close the fd. No victim action is involved.\nS:U - The corruption is confined to the kernel\u0027s own heap/page allocator within the same security authority; there is no VM, IOMMU, or hypervisor boundary crossed.\nC:H - The double free lets the attacker reclaim the chunk with a chosen object and then have the kernel free it while still in use, producing a use-after-free with overlapping allocations that can be leveraged to read arbitrary kernel memory (credentials, keys, KASLR data).\nI:H - Freeing an in-use, attacker-sprayed object (or a costly-order page, giving cross-cache/physical-page reuse) yields a write primitive over kernel objects, enabling control-flow hijack and privilege escalation to root.\nA:H - Even unweaponized, the double free corrupts the SLUB freelist or page allocator and reliably panics the kernel (KASAN reports it as a `double-free` BUG), and the attacker can repeat it across many binder fds."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:07:10.905Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c301ec61ce6f16e21a36b99225ca8a20c1591e10"
        },
        {
          "url": "https://git.kernel.org/stable/c/0390633979969c54c0ce6a198d6f45cdbe2c84b1"
        },
        {
          "url": "https://git.kernel.org/stable/c/b781e5635a3398e2b64440371233c2c5102cd6cb"
        },
        {
          "url": "https://git.kernel.org/stable/c/3ebcd3460cad351f198c39c6edb4af519a0ed934"
        }
      ],
      "title": "binder: fix double-free in dbitmap",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40028",
    "datePublished": "2025-10-28T09:32:35.681Z",
    "dateReserved": "2025-04-16T07:20:57.152Z",
    "dateUpdated": "2026-08-05T12:07:10.905Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-40028",
      "date": "2026-09-16",
      "epss": "0.00142",
      "percentile": "0.03912"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-40028\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-10-28T10:15:42.447\",\"lastModified\":\"2026-07-30T06:24:06.920\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbinder: fix double-free in dbitmap\\n\\nA process might fail to allocate a new bitmap when trying to expand its\\nproc-\u003edmap. In that case, dbitmap_grow() fails and frees the old bitmap\\nvia dbitmap_free(). However, the driver calls dbitmap_free() again when\\nthe same process terminates, leading to a double-free error:\\n\\n  ==================================================================\\n  BUG: KASAN: double-free in binder_proc_dec_tmpref+0x2e0/0x55c\\n  Free of addr ffff00000b7c1420 by task kworker/9:1/209\\n\\n  CPU: 9 UID: 0 PID: 209 Comm: kworker/9:1 Not tainted 6.17.0-rc6-dirty #5 PREEMPT\\n  Hardware name: linux,dummy-virt (DT)\\n  Workqueue: events binder_deferred_func\\n  Call trace:\\n   kfree+0x164/0x31c\\n   binder_proc_dec_tmpref+0x2e0/0x55c\\n   binder_deferred_func+0xc24/0x1120\\n   process_one_work+0x520/0xba4\\n  [...]\\n\\n  Allocated by task 448:\\n   __kmalloc_noprof+0x178/0x3c0\\n   bitmap_zalloc+0x24/0x30\\n   binder_open+0x14c/0xc10\\n  [...]\\n\\n  Freed by task 449:\\n   kfree+0x184/0x31c\\n   binder_inc_ref_for_node+0xb44/0xe44\\n   binder_transaction+0x29b4/0x7fbc\\n   binder_thread_write+0x1708/0x442c\\n   binder_ioctl+0x1b50/0x2900\\n  [...]\\n  ==================================================================\\n\\nFix this issue by marking proc-\u003emap NULL in dbitmap_free().\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/android/dbitmap.h\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"15d9da3f818cae676f822a04407d3c17b53357d2\",\"lessThan\":\"c301ec61ce6f16e21a36b99225ca8a20c1591e10\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"15d9da3f818cae676f822a04407d3c17b53357d2\",\"lessThan\":\"0390633979969c54c0ce6a198d6f45cdbe2c84b1\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"15d9da3f818cae676f822a04407d3c17b53357d2\",\"lessThan\":\"b781e5635a3398e2b64440371233c2c5102cd6cb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"15d9da3f818cae676f822a04407d3c17b53357d2\",\"lessThan\":\"3ebcd3460cad351f198c39c6edb4af519a0ed934\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/android/dbitmap.h\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.11\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.11\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.52\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.16.12\",\"lessThanOrEqual\":\"6.16.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.17.2\",\"lessThanOrEqual\":\"6.17.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"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\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0390633979969c54c0ce6a198d6f45cdbe2c84b1\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3ebcd3460cad351f198c39c6edb4af519a0ed934\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b781e5635a3398e2b64440371233c2c5102cd6cb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c301ec61ce6f16e21a36b99225ca8a20c1591e10\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "None",
      "current_release_date": "2026-06-30T10:15:24+00:00",
      "cve": "CVE-2025-40028",
      "id": "CVE-2025-40028",
      "initial_release_date": "2025-10-28T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: binder: fix double-free in dbitmap",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40028.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-28T16:56:14Z",
      "cve": "CVE-2025-40028",
      "id": "CVE-2025-40028",
      "initial_release_date": "2025-10-29T00:25:42Z",
      "product_status:known_not_affected": "514",
      "product_status:recommended": "6",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-40028",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-40028.json",
      "version": "9"
    }
  }
}