CVE-2025-38457

{"id": "CVE-2025-38457", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-07-25T16:15:31.403", "references": [{"url": "https://git.kernel.org/stable/c/23c165dde88eac405eebb59051ea1fe139a45803", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/25452638f133ac19d75af3f928327d8016952c8e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4c691d1b6b6dbd73f30ed9ee7da05f037b0c49af", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8ecd651ef24ab50123692a4e3e25db93cb11602a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/90436e72c9622c2f70389070088325a3232d339f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/923a276c74e25073ae391e930792ac86a9f77f1e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e28a383d6485c3bb51dc5953552f76c4dea33eea", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ffdde7bf5a439aaa1955ebd581f5c64ab1533963", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html", "tags": ["Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html", "tags": ["Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "[email protected]", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: Abort __tc_modify_qdisc if parent class does not exist\n\nLion's patch [1] revealed an ancient bug in the qdisc API.\nWhenever a user creates/modifies a qdisc specifying as a parent another\nqdisc, the qdisc API will, during grafting, detect that the user is\nnot trying to attach to a class and reject. However grafting is\nperformed after qdisc_create (and thus the qdiscs' init callback) is\nexecuted. In qdiscs that eventually call qdisc_tree_reduce_backlog\nduring init or change (such as fq, hhf, choke, etc), an issue\narises. For example, executing the following commands:\n\nsudo tc qdisc add dev lo root handle a: htb default 2\nsudo tc qdisc add dev lo parent a: handle beef fq\n\nQdiscs such as fq, hhf, choke, etc unconditionally invoke\nqdisc_tree_reduce_backlog() in their control path init() or change() which\nthen causes a failure to find the child class; however, that does not stop\nthe unconditional invocation of the assumed child qdisc's qlen_notify with\na null class. All these qdiscs make the assumption that class is non-null.\n\nThe solution is ensure that qdisc_leaf() which looks up the parent\nclass, and is invoked prior to qdisc_create(), should return failure on\nnot finding the class.\nIn this patch, we leverage qdisc_leaf to return ERR_PTRs whenever the\nparentid doesn't correspond to a class, so that we can detect it\nearlier on and abort before qdisc_create is called.\n\n[1] https://lore.kernel.org/netdev/[email protected]/"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/sched: Abort __tc_modify_qdisc si la clase padre no existe. El parche de Lion [1] revel\u00f3 un error antiguo en la API de qdisc. Siempre que un usuario crea o modifica una qdisc que especifica otra qdisc como padre, la API de qdisc detecta, durante el injerto, que el usuario no intenta asociarse a una clase y lo rechaza. Sin embargo, el injerto se realiza despu\u00e9s de ejecutar qdisc_create (y, por lo tanto, la devoluci\u00f3n de llamada de inicio de la qdisc). En las qdisc que eventualmente llaman a qdisc_tree_reduce_backlog durante la inicializaci\u00f3n o el cambio (como fq, hhf, choke, etc.), surge un problema. Por ejemplo, al ejecutar los siguientes comandos: sudo tc qdisc add dev lo root handle a: htb default 2 sudo tc qdisc add dev lo parent a: handle beef fq Las Qdisc como fq, hhf, choke, etc., invocan incondicionalmente qdisc_tree_reduce_backlog() en su ruta de control init() o change(), lo que provoca un error al no encontrar la clase hija; sin embargo, esto no detiene la invocaci\u00f3n incondicional de qlen_notify de la qdisc hija asumida con una clase nula. Todas estas qdisc asumen que la clase no es nula. La soluci\u00f3n es garantizar que qdisc_leaf(), que busca la clase padre y se invoca antes que qdisc_create(), devuelva un error al no encontrar la clase. En este parche, aprovechamos qdisc_leaf para devolver ERR_PTR siempre que el parentid no corresponda a una clase, de modo que podamos detectarlo antes y abortar antes de que se llame a qdisc_create. [1] https://lore.kernel.org/netdev/[email protected]/"}], "lastModified": "2025-12-22T21:49:38.683", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "092812DB-392E-4683-B1DB-4F3057267FC0", "versionEndExcluding": "5.4.296", "versionStartIncluding": "2.6.20"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0E73A49A-F9B2-470F-91B2-6FAB6239BDB6", "versionEndExcluding": "5.10.240", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3CE0FB9A-DBE8-48B6-BF6E-3C724A4991E3", "versionEndExcluding": "5.15.189", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D8DA1166-5C95-475E-BF65-1DF621968E96", "versionEndExcluding": "6.1.146", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B369699C-E0E6-42A4-BDEE-8E676ECEF6AA", "versionEndExcluding": "6.6.99", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "18D57670-11F8-4B5A-AD56-EA32DD0F44E1", "versionEndExcluding": "6.12.39", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F9C46937-5FA9-4335-AD7B-E7FC29453CE1", "versionEndExcluding": "6.15.7", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6D4894DB-CCFE-4602-B1BF-3960B2E19A01"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "09709862-E348-4378-8632-5A7813EDDC86"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "415BF58A-8197-43F5-B3D7-D1D63057A26E"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A0517869-312D-4429-80C2-561086E1421C"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "85421F4E-C863-4ABF-B4B4-E887CC2F7F92"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}