CVE-2025-40094

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-40094", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.163Z", "datePublished": "2025-10-30T09:48:02.446Z", "dateUpdated": "2026-08-05T12:07:45.475Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:07:45.475Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_acm: Refactor bind path to use __free()\n\nAfter an bind/unbind cycle, the acm->notify_req is left stale. If a\nsubsequent bind fails, the unified error label attempts to free this\nstale request, leading to a NULL pointer dereference when accessing\nep->ops->free_request.\n\nRefactor the error handling in the bind path to use the __free()\nautomatic cleanup mechanism.\n\nUnable to handle kernel NULL pointer dereference at virtual address 0000000000000020\nCall trace:\n usb_ep_free_request+0x2c/0xec\n gs_free_req+0x30/0x44\n acm_bind+0x1b8/0x1f4\n usb_add_function+0xcc/0x1f0\n configfs_composite_bind+0x468/0x588\n gadget_bind_driver+0x104/0x270\n really_probe+0x190/0x374\n __driver_probe_device+0xa0/0x12c\n driver_probe_device+0x3c/0x218\n __device_attach_driver+0x14c/0x188\n bus_for_each_drv+0x10c/0x168\n __device_attach+0xfc/0x198\n device_initial_probe+0x14/0x24\n bus_probe_device+0x94/0x11c\n device_add+0x268/0x48c\n usb_add_gadget+0x198/0x28c\n dwc3_gadget_init+0x700/0x858\n __dwc3_set_mode+0x3cc/0x664\n process_scheduled_works+0x1d8/0x488\n worker_thread+0x244/0x334\n kthread+0x114/0x1bc\n ret_from_fork+0x10/0x20"}], "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 bind/unbind/re-bind sequence that creates and then dereferences the stale `acm->notify_req` is driven entirely by local writes to `/sys/kernel/config/usb_gadget/<g>/UDC` (or legacy gadget module load); no USB traffic from an attached host is needed, so the bug is reachable through local filesystem/syscall access rather than requiring physical port access.\nAC:L - The attacker deterministically controls every step \u2014 the successful first bind, the unbind that leaves `acm->notify_req` dangling, and the forced failure of the next bind by exhausting `usb_interface_id()`/`usb_ep_autoconfig()` through functions added to the config between cycles \u2014 plus the heap spray that reclaims the freed `usb_request`. No race or uncontrolled condition is involved.\nPR:L - Only write access to the USB gadget configfs tree is required; `acm_bind()` performs no capability check, and on Android and embedded/industrial deployments USB function switching is routinely delegated to non-root system/daemon accounts that own that tree.\nUI:N - The attacker performs all configfs writes itself; no cable plug event, victim action, or interaction with another user is required to reach the stale free.\nS:U - The dangling-pointer free corrupts kernel heap state within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - `gs_free_req()` reads `req->buf` out of the reclaimed `struct dwc3_request` slab and `ep->ops` out of a freed `struct dwc3_ep`, so an attacker who grooms those caches gains object-overlap and arbitrary-free primitives that are readily converted into kernel memory disclosure.\nI:H - `kfree()` of an attacker-controlled pointer read from the freed request, a double free through `dwc3_gadget_ep_free_request()`, and an indirect call through a reclaimable `ep->ops` table together yield classic heap-corruption primitives leading to arbitrary write and privilege escalation.\nA:H - The observed effect is a kernel oops \u2014 NULL/garbage `ep->ops` dereference in `usb_ep_free_request()` \u2014 and the double free independently causes slab corruption and panic, which the attacker can trigger repeatedly."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/usb/gadget/function/f_acm.c"], "versions": [{"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "c5d116862dd3ed162d079738a5ebddf9fceea850", "status": "affected", "versionType": "git"}, {"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "2b1546f7c5fc6c44555a8e7a2b34229d1dcd2175", "status": "affected", "versionType": "git"}, {"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "e348d18fb0124b662cfefb3001733b49da428215", "status": "affected", "versionType": "git"}, {"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "201a66d8e6630762e760e1d78f1d149da1691e7b", "status": "affected", "versionType": "git"}, {"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "c4301e4dd6b32faccb744f1c2320e64235b68d3b", "status": "affected", "versionType": "git"}, {"version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "lessThan": "47b2116e54b4a854600341487e8b55249e926324", "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/usb/gadget/function/f_acm.c"], "versions": [{"version": "2.6.27", "status": "affected"}, {"version": "0", "lessThan": "2.6.27", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.196", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.158", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.114", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.55", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.17.5", "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": "2.6.27", "versionEndExcluding": "5.15.196"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.27", "versionEndExcluding": "6.1.158"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.27", "versionEndExcluding": "6.6.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.27", "versionEndExcluding": "6.12.55"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.27", "versionEndExcluding": "6.17.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.27", "versionEndExcluding": "6.18"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/c5d116862dd3ed162d079738a5ebddf9fceea850"}, {"url": "https://git.kernel.org/stable/c/2b1546f7c5fc6c44555a8e7a2b34229d1dcd2175"}, {"url": "https://git.kernel.org/stable/c/e348d18fb0124b662cfefb3001733b49da428215"}, {"url": "https://git.kernel.org/stable/c/201a66d8e6630762e760e1d78f1d149da1691e7b"}, {"url": "https://git.kernel.org/stable/c/c4301e4dd6b32faccb744f1c2320e64235b68d3b"}, {"url": "https://git.kernel.org/stable/c/47b2116e54b4a854600341487e8b55249e926324"}], "title": "usb: gadget: f_acm: Refactor bind path to use __free()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/usb/gadget/function/f_acm.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "c5d116862dd3ed162d079738a5ebddf9fceea850", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}, {"lessThan": "2b1546f7c5fc6c44555a8e7a2b34229d1dcd2175", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}, {"lessThan": "e348d18fb0124b662cfefb3001733b49da428215", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}, {"lessThan": "201a66d8e6630762e760e1d78f1d149da1691e7b", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}, {"lessThan": "c4301e4dd6b32faccb744f1c2320e64235b68d3b", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}, {"lessThan": "47b2116e54b4a854600341487e8b55249e926324", "status": "affected", "version": "1f1ba11b64947051fc32aa15fcccef6463b433f7", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/usb/gadget/function/f_acm.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.27"}, {"lessThan": "2.6.27", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.196", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.158", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.114", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.55", "versionType": "semver"}, {"lessThanOrEqual": "6.17.*", "status": "unaffected", "version": "6.17.5", "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\nusb: gadget: f_acm: Refactor bind path to use __free()\n\nAfter an bind/unbind cycle, the acm->notify_req is left stale. If a\nsubsequent bind fails, the unified error label attempts to free this\nstale request, leading to a NULL pointer dereference when accessing\nep->ops->free_request.\n\nRefactor the error handling in the bind path to use the __free()\nautomatic cleanup mechanism.\n\nUnable to handle kernel NULL pointer dereference at virtual address 0000000000000020\nCall trace:\n usb_ep_free_request+0x2c/0xec\n gs_free_req+0x30/0x44\n acm_bind+0x1b8/0x1f4\n usb_add_function+0xcc/0x1f0\n configfs_composite_bind+0x468/0x588\n gadget_bind_driver+0x104/0x270\n really_probe+0x190/0x374\n __driver_probe_device+0xa0/0x12c\n driver_probe_device+0x3c/0x218\n __device_attach_driver+0x14c/0x188\n bus_for_each_drv+0x10c/0x168\n __device_attach+0xfc/0x198\n device_initial_probe+0x14/0x24\n bus_probe_device+0x94/0x11c\n device_add+0x268/0x48c\n usb_add_gadget+0x198/0x28c\n dwc3_gadget_init+0x700/0x858\n __dwc3_set_mode+0x3cc/0x664\n process_scheduled_works+0x1d8/0x488\n worker_thread+0x244/0x334\n kthread+0x114/0x1bc\n ret_from_fork+0x10/0x20"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nusb: gadget: f_acm: Refactorizar la ruta de enlace para usar __free()\n\nDespu\u00e9s de un ciclo de enlace/desenlace, el acm->notify_req queda obsoleto. Si un enlace posterior falla, la etiqueta de error unificada intenta liberar esta solicitud obsoleta, lo que lleva a una desreferencia de puntero NULL al acceder a ep->ops->free_request.\n\nRefactorizar el manejo de errores en la ruta de enlace para usar el mecanismo de limpieza autom\u00e1tica __free().\n\nNo se puede manejar la desreferencia de puntero NULL del kernel en la direcci\u00f3n virtual 0000000000000020\nRastro de llamada:\n usb_ep_free_request+0x2c/0xec\n gs_free_req+0x30/0x44\n acm_bind+0x1b8/0x1f4\n usb_add_function+0xcc/0x1f0\n configfs_composite_bind+0x468/0x588\n gadget_bind_driver+0x104/0x270\n really_probe+0x190/0x374\n __driver_probe_device+0xa0/0x12c\n driver_probe_device+0x3c/0x218\n __device_attach_driver+0x14c/0x188\n bus_for_each_drv+0x10c/0x168\n __device_attach+0xfc/0x198\n device_initial_probe+0x14/0x24\n bus_probe_device+0x94/0x11c\n device_add+0x268/0x48c\n usb_add_gadget+0x198/0x28c\n dwc3_gadget_init+0x700/0x858\n __dwc3_set_mode+0x3cc/0x664\n process_scheduled_works+0x1d8/0x488\n worker_thread+0x244/0x334\n kthread+0x114/0x1bc\n ret_from_fork+0x10/0x20"}], "id": "CVE-2025-40094", "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": "2025-10-30T10:15:33.900", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/201a66d8e6630762e760e1d78f1d149da1691e7b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2b1546f7c5fc6c44555a8e7a2b34229d1dcd2175"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/47b2116e54b4a854600341487e8b55249e926324"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c4301e4dd6b32faccb744f1c2320e64235b68d3b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c5d116862dd3ed162d079738a5ebddf9fceea850"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e348d18fb0124b662cfefb3001733b49da428215"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "usb: gadget: f_acm: Refactor bind path to use __free()", "id": "2407329", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2407329"}, "csaw": false, "details": ["No description is available for this CVE."], "name": "CVE-2025-40094", "public_date": "2025-10-30T09:48:02Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-40094\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40094\nhttps://git.kernel.org/stable/c/201a66d8e6630762e760e1d78f1d149da1691e7b\nhttps://git.kernel.org/stable/c/2b1546f7c5fc6c44555a8e7a2b34229d1dcd2175\nhttps://git.kernel.org/stable/c/47b2116e54b4a854600341487e8b55249e926324\nhttps://git.kernel.org/stable/c/c4301e4dd6b32faccb744f1c2320e64235b68d3b\nhttps://git.kernel.org/stable/c/c5d116862dd3ed162d079738a5ebddf9fceea850\nhttps://git.kernel.org/stable/c/e348d18fb0124b662cfefb3001733b49da428215"]}

{"created": "2025-10-30T14:37:23.205499+00:00", "updated": "2025-10-30T14:37:23.205523+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}