CVE-2025-40028

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-40028", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.152Z", "datePublished": "2025-10-28T09:32:35.681Z", "dateUpdated": "2026-08-05T12:07:10.905Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:07:10.905Z"}, "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->dmap. 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->map NULL in dbitmap_free()."}], "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 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's 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."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/android/dbitmap.h"], "versions": [{"version": "15d9da3f818cae676f822a04407d3c17b53357d2", "lessThan": "c301ec61ce6f16e21a36b99225ca8a20c1591e10", "status": "affected", "versionType": "git"}, {"version": "15d9da3f818cae676f822a04407d3c17b53357d2", "lessThan": "0390633979969c54c0ce6a198d6f45cdbe2c84b1", "status": "affected", "versionType": "git"}, {"version": "15d9da3f818cae676f822a04407d3c17b53357d2", "lessThan": "b781e5635a3398e2b64440371233c2c5102cd6cb", "status": "affected", "versionType": "git"}, {"version": "15d9da3f818cae676f822a04407d3c17b53357d2", "lessThan": "3ebcd3460cad351f198c39c6edb4af519a0ed934", "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/android/dbitmap.h"], "versions": [{"version": "6.11", "status": "affected"}, {"version": "0", "lessThan": "6.11", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.52", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.16.12", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.17.2", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18", "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": "6.11", "versionEndExcluding": "6.12.52"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.16.12"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.17.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11", "versionEndExcluding": "6.18"}]}]}], "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"}}}}

{}

{"affected": [{"affectedData": [{"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"}, {"lessThan": "0390633979969c54c0ce6a198d6f45cdbe2c84b1", "status": "affected", "version": "15d9da3f818cae676f822a04407d3c17b53357d2", "versionType": "git"}, {"lessThan": "b781e5635a3398e2b64440371233c2c5102cd6cb", "status": "affected", "version": "15d9da3f818cae676f822a04407d3c17b53357d2", "versionType": "git"}, {"lessThan": "3ebcd3460cad351f198c39c6edb4af519a0ed934", "status": "affected", "version": "15d9da3f818cae676f822a04407d3c17b53357d2", "versionType": "git"}]}, {"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"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "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->dmap. 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->map NULL in dbitmap_free()."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nbinder: correcci\u00f3n de doble liberaci\u00f3n en dbitmap\n\nUn proceso podr\u00eda fallar al asignar un nuevo bitmap al intentar expandir su proc->dmap. En ese caso, dbitmap_grow() falla y libera el bitmap antiguo a trav\u00e9s de dbitmap_free(). Sin embargo, el controlador llama a dbitmap_free() de nuevo cuando el mismo proceso termina, lo que lleva a un error de doble liberaci\u00f3n:\n\n ==================================================================\n BUG: KASAN: doble liberaci\u00f3n en binder_proc_dec_tmpref+0x2e0/0x55c\n Liberaci\u00f3n de direcci\u00f3n ffff00000b7c1420 por tarea 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 Rastreo de llamadas:\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 Asignado por tarea 448:\n __kmalloc_noprof+0x178/0x3c0\n bitmap_zalloc+0x24/0x30\n binder_open+0x14c/0xc10\n [...]\n\n Liberado por tarea 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\nSolucione este problema marcando proc->map como NULL en dbitmap_free()."}], "id": "CVE-2025-40028", "lastModified": "2026-10-19T21:10:00.160", "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": "2025-10-28T10:15:42.447", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "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"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "kernel: binder: fix double-free in dbitmap", "id": "2406714", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2406714"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["No description is available for this CVE."], "name": "CVE-2025-40028", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-10-28T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-40028\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40028\nhttps://lore.kernel.org/linux-cve-announce/2025102841-CVE-2025-40028-f52b@gregkh/T"], "threat_severity": "Moderate"}

{"created": "2025-10-29T10:58:47.568863+00:00", "updated": "2025-10-29T10:58:47.568888+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}