{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-37949", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.972Z", "datePublished": "2025-05-20T16:01:45.242Z", "dateUpdated": "2025-11-03T19:57:40.135Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2025-06-04T12:57:34.373Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxenbus: Use kref to track req lifetime\n\nMarek reported seeing a NULL pointer fault in the xenbus_thread\ncallstack:\nBUG: kernel NULL pointer dereference, address: 0000000000000000\nRIP: e030:__wake_up_common+0x4c/0x180\nCall Trace:\n <TASK>\n __wake_up_common_lock+0x82/0xd0\n process_msg+0x18e/0x2f0\n xenbus_thread+0x165/0x1c0\n\nprocess_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a\nthin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems\nlike it was xs_wake_up() in this case.\n\nIt seems like req may have woken up the xs_wait_for_reply(), which\nkfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed\ndata.\n\nLinux Device Drivers 2nd edition states:\n\"Normally, a wake_up call can cause an immediate reschedule to happen,\nmeaning that other processes might run before wake_up returns.\"\n... which would match the behaviour observed.\n\nChange to keeping two krefs on each request. One for the caller, and\none for xenbus_thread. Each will kref_put() when finished, and the last\nwill free it.\n\nThis use of kref matches the description in\nDocumentation/core-api/kref.rst"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/xen/xenbus/xenbus.h", "drivers/xen/xenbus/xenbus_comms.c", "drivers/xen/xenbus/xenbus_dev_frontend.c", "drivers/xen/xenbus/xenbus_xs.c"], "versions": [{"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "0e94a246bb6d9538010b6c02d2b1d4717a97b2e5", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "f1bcac367bc95631afbb918348f30dec887d0e1b", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "4d260a5558df4650eb87bc41b2c9ac2d6b2ba447", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "8b02f85e84dc6f7c150cef40ddb69af5a25659e5", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "cbfaf46b88a4c01b64c4186cdccd766c19ae644c", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "8e9c8a0393b5f85f1820c565ab8105660f4e8f92", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "2466b0f66795c3c426cacc8998499f38031dbb59", "status": "affected", "versionType": "git"}, {"version": "fd8aa9095a95c02dcc35540a263267c29b8fda9d", "lessThan": "1f0304dfd9d217c2f8b04a9ef4b3258a66eedd27", "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/xen/xenbus/xenbus.h", "drivers/xen/xenbus/xenbus_comms.c", "drivers/xen/xenbus/xenbus_dev_frontend.c", "drivers/xen/xenbus/xenbus_xs.c"], "versions": [{"version": "4.11", "status": "affected"}, {"version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver"}, {"version": "5.4.294", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.238", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.183", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.139", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.91", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.29", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.14.7", "lessThanOrEqual": "6.14.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.15", "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": "4.11", "versionEndExcluding": "5.4.294"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.10.238"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.1.139"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.6.91"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.12.29"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.14.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.15"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0e94a246bb6d9538010b6c02d2b1d4717a97b2e5"}, {"url": "https://git.kernel.org/stable/c/f1bcac367bc95631afbb918348f30dec887d0e1b"}, {"url": "https://git.kernel.org/stable/c/4d260a5558df4650eb87bc41b2c9ac2d6b2ba447"}, {"url": "https://git.kernel.org/stable/c/8b02f85e84dc6f7c150cef40ddb69af5a25659e5"}, {"url": "https://git.kernel.org/stable/c/cbfaf46b88a4c01b64c4186cdccd766c19ae644c"}, {"url": "https://git.kernel.org/stable/c/8e9c8a0393b5f85f1820c565ab8105660f4e8f92"}, {"url": "https://git.kernel.org/stable/c/2466b0f66795c3c426cacc8998499f38031dbb59"}, {"url": "https://git.kernel.org/stable/c/1f0304dfd9d217c2f8b04a9ef4b3258a66eedd27"}], "title": "xenbus: Use kref to track req lifetime", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"title": "CVE Program Container", "references": [{"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T19:57:40.135Z"}}]}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxenbus: Use kref to track req lifetime\n\nMarek reported seeing a NULL pointer fault in the xenbus_thread\ncallstack:\nBUG: kernel NULL pointer dereference, address: 0000000000000000\nRIP: e030:__wake_up_common+0x4c/0x180\nCall Trace:\n <TASK>\n __wake_up_common_lock+0x82/0xd0\n process_msg+0x18e/0x2f0\n xenbus_thread+0x165/0x1c0\n\nprocess_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a\nthin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems\nlike it was xs_wake_up() in this case.\n\nIt seems like req may have woken up the xs_wait_for_reply(), which\nkfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed\ndata.\n\nLinux Device Drivers 2nd edition states:\n\"Normally, a wake_up call can cause an immediate reschedule to happen,\nmeaning that other processes might run before wake_up returns.\"\n... which would match the behaviour observed.\n\nChange to keeping two krefs on each request. One for the caller, and\none for xenbus_thread. Each will kref_put() when finished, and the last\nwill free it.\n\nThis use of kref matches the description in\nDocumentation/core-api/kref.rst"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: xenbus: Usar kref para rastrear el tiempo de vida de req. Marek inform\u00f3 haber visto un fallo de puntero nulo en la pila de llamadas xenbus_thread: ERROR: desreferencia de puntero nulo del kernel, direcci\u00f3n: 0000000000000000 RIP: e030:__wake_up_common+0x4c/0x180 Rastreo de llamadas: __wake_up_common_lock+0x82/0xd0 process_msg+0x18e/0x2f0 xenbus_thread+0x165/0x1c0 process_msg+0x18e es req-&gt;cb(req). req-&gt;cb est\u00e1 configurado como xs_wake_up(), una envoltura ligera alrededor de wake_up(), o xenbus_dev_queue_reply(). Parece que en este caso era xs_wake_up(). Parece que req pudo haber despertado xs_wait_for_reply(), que liber\u00f3 la solicitud. Cuando xenbus_thread se reanuda, falla en los datos con ceros. La segunda edici\u00f3n de los controladores de dispositivos de Linux indica: \u00abNormalmente, una llamada wake_up puede provocar una reprogramaci\u00f3n inmediata, lo que significa que otros procesos podr\u00edan ejecutarse antes de que wake_up regrese\u00bb. ... lo cual coincidir\u00eda con el comportamiento observado. Se recomienda mantener dos krefs en cada solicitud: uno para el que realiza la llamada y otro para xenbus_thread. Cada uno ejecutar\u00e1 kref_put() al finalizar, y el \u00faltimo lo liberar\u00e1. Este uso de kref coincide con la descripci\u00f3n en Documentation/core-api/kref.rst."}], "id": "CVE-2025-37949", "lastModified": "2025-11-03T20:18:43.063", "metrics": {}, "published": "2025-05-20T16:15:32.920", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0e94a246bb6d9538010b6c02d2b1d4717a97b2e5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1f0304dfd9d217c2f8b04a9ef4b3258a66eedd27"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2466b0f66795c3c426cacc8998499f38031dbb59"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4d260a5558df4650eb87bc41b2c9ac2d6b2ba447"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8b02f85e84dc6f7c150cef40ddb69af5a25659e5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8e9c8a0393b5f85f1820c565ab8105660f4e8f92"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/cbfaf46b88a4c01b64c4186cdccd766c19ae644c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f1bcac367bc95631afbb918348f30dec887d0e1b"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: xenbus: Use kref to track req lifetime", "id": "2367590", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2367590"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["In the Linux kernel, the following vulnerability has been resolved:\nxenbus: Use kref to track req lifetime\nMarek reported seeing a NULL pointer fault in the xenbus_thread\ncallstack:\nBUG: kernel NULL pointer dereference, address: 0000000000000000\nRIP: e030:__wake_up_common+0x4c/0x180\nCall Trace:\n<TASK>\n__wake_up_common_lock+0x82/0xd0\nprocess_msg+0x18e/0x2f0\nxenbus_thread+0x165/0x1c0\nprocess_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a\nthin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems\nlike it was xs_wake_up() in this case.\nIt seems like req may have woken up the xs_wait_for_reply(), which\nkfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed\ndata.\nLinux Device Drivers 2nd edition states:\n\"Normally, a wake_up call can cause an immediate reschedule to happen,\nmeaning that other processes might run before wake_up returns.\"\n... which would match the behaviour observed.\nChange to keeping two krefs on each request. One for the caller, and\none for xenbus_thread. Each will kref_put() when finished, and the last\nwill free it.\nThis use of kref matches the description in\nDocumentation/core-api/kref.rst"], "name": "CVE-2025-37949", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-05-20T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-37949\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-37949\nhttps://lore.kernel.org/linux-cve-announce/2025052000-CVE-2025-37949-c272@gregkh/T"], "statement": "Local issue in Xen guest kernel requiring privileged access. No remote vector or privilege escalation; only potential DoS via NULL dereference.", "threat_severity": "Moderate"}