{"id":"CVE-2026-89951","published":"2026-09-16T11:17:05.267","lastModified":"2026-09-16T15:18:19.990","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: fix stale receive device on merged fragments\n\nFragment reassembly reuses the skb from the highest-numbered buffered\nfragment as the merged packet. When that fragment was received on a hard\ninterface which is deleted before the chain completes, the merged skb can\nre-enter the receive path with a stale skb->dev and skb_iif.\n\nbatadv_batman_skb_recv() passes such merged packets through the normal\nreceive handlers again. DAT and bridge loop avoidance both derive the ARP\nheader length from skb->dev, so they can dereference the freed net_device\nbefore the packet reaches the local mesh interface.\n\nRefresh the receive device metadata from the current receive device before\nrunning the packet handlers. This keeps internally reinjected merged\nfragments consistent with the normal receive path after hard interface\nteardown.","cvssScore":8.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/2dffc8c44b6e3347b3719c6419c07b4a18fea895","tags":[]},{"url":"https://git.kernel.org/stable/c/63d86250fa7cbe22451369bd1c0881dfc8190958","tags":[]},{"url":"https://git.kernel.org/stable/c/6df64825f8b199921120c685af2abca14b077331","tags":[]},{"url":"https://git.kernel.org/stable/c/a2c272da99c2077088083c14961cf2f1e4506995","tags":[]},{"url":"https://git.kernel.org/stable/c/ad46c907d7d9975a285c1e89a4adde652eaa93f5","tags":[]},{"url":"https://git.kernel.org/stable/c/e91d2cc7441d89a45bad73ad9789159c7441cb80","tags":[]},{"url":"https://git.kernel.org/stable/c/f4b4ae763b5d59319fad62a00c76676758e7dafa","tags":[]},{"url":"https://git.kernel.org/stable/c/f830c2dfc1431764db9256b3d5db1695fc9a7f56","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":{"summary":"This vulnerability in the batman-adv module of the Linux kernel allows for potential data corruption and denial of service when handling fragmented packets, especially after a hard interface deletion.","exploitability":"Exploitation requires the attacker to send fragmented packets to a target system with a deleted hard interface, making it moderately difficult and dependent on specific network conditions.","blast_radius":"If exploited, the vulnerability could lead to data corruption, bridge loop issues, and potential denial of service for the affected network segment.","remediation":"Upgrade to the Linux kernel version 6.1.15 or later.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["dos","network","kernel"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-09-30T09:14:21.296Z"}}