CVE-2024-35839

{"id": "CVE-2024-35839", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "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": "2024-05-17T15:15:21.017", "references": [{"url": "https://git.kernel.org/stable/c/544add1f1cfb78c3dfa3e6edcf4668f6be5e730c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/7ae19ee81ca56b13c50a78de6c47d5b8fdc9d97b", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/9325e3188a9cf3f69fc6f32af59844bbc5b90547", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/9874808878d9eed407e3977fd11fee49de1e1d86", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/544add1f1cfb78c3dfa3e6edcf4668f6be5e730c", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/7ae19ee81ca56b13c50a78de6c47d5b8fdc9d97b", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/9325e3188a9cf3f69fc6f32af59844bbc5b90547", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/9874808878d9eed407e3977fd11fee49de1e1d86", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: bridge: replace physindev with physinif in nf_bridge_info\n\nAn skb can be added to a neigh->arp_queue while waiting for an arp\nreply. Where original skb's skb->dev can be different to neigh's\nneigh->dev. For instance in case of bridging dnated skb from one veth to\nanother, the skb would be added to a neigh->arp_queue of the bridge.\n\nAs skb->dev can be reset back to nf_bridge->physindev and used, and as\nthere is no explicit mechanism that prevents this physindev from been\nfreed under us (for instance neigh_flush_dev doesn't cleanup skbs from\ndifferent device's neigh queue) we can crash on e.g. this stack:\n\narp_process\n neigh_update\n skb = __skb_dequeue(&neigh->arp_queue)\n neigh_resolve_output(..., skb)\n ...\n br_nf_dev_xmit\n br_nf_pre_routing_finish_bridge_slow\n skb->dev = nf_bridge->physindev\n br_handle_frame_finish\n\nLet's use plain ifindex instead of net_device link. To peek into the\noriginal net_device we will use dev_get_by_index_rcu(). Thus either we\nget device and are safe to use it or we don't get it and drop skb."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: bridge: reemplace physindev con physinif en nf_bridge_info. Se puede agregar un skb a neigh->arp_queue mientras se espera una respuesta de arp. Donde skb->dev del skb original puede ser diferente al neigh->dev de neigh. Por ejemplo, en el caso de unir un skb designado de un veth a otro, el skb se agregar\u00eda a un vecino->arp_queue del puente. Como skb->dev se puede restablecer a nf_bridge->physindev y usarse, y como no existe un mecanismo expl\u00edcito que impida que este physindev se libere bajo nuestra responsabilidad (por ejemplo, neigh_flush_dev no limpia skbs de la cola vecina de diferentes dispositivos), podemos crashear, por ejemplo, en esta pila: arp_process neigh_update skb = __skb_dequeue(&neigh->arp_queue) neigh_resolve_output(..., skb) ... br_nf_dev_xmit br_nf_pre_routing_finish_bridge_slow skb->dev = nf_bridge->physindev br_handle_frame_finish Usemos ifindex simple en lugar de enlace net_device. Para echar un vistazo al net_device original usaremos dev_get_by_index_rcu(). Por lo tanto, o obtenemos el dispositivo y podemos usarlo con seguridad o no lo obtenemos y eliminamos skb."}], "lastModified": "2025-09-24T21:02:31.860", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CEA7D262-0A5C-47C0-BA3A-5EC1E08EE6B2", "versionEndExcluding": "6.1.75", "versionStartIncluding": "4.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5C6B50A6-3D8B-4CE2-BDCC-A098609CBA14", "versionEndExcluding": "6.6.14", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7229C448-E0C9-488B-8939-36BA5254065E", "versionEndExcluding": "6.7.2", "versionStartIncluding": "6.7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}