{"id":"CVE-2026-99066","title":"can: dev: init_can_skb(): restore skb header initialization","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: dev: init_can_skb(): restore skb header initialization\n\nCommit 9f10374bb024 (\"can: remove private CAN skb headroom infrastructure\")\nremoved the skb_reset_mac_heade…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 9f10374bb024593a611e6845847f0444841a231b < 8078375dfd0baecd9f1b7b06bb2d6f88d7cb8632","Linux >= 9f10374bb024593a611e6845847f0444841a231b < 0a04c0cb8606ff88399489d03ef255afe90d0d5f","Linux 7.0"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T12:23:09.516Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99066","references":[{"url":"https://git.kernel.org/stable/c/8078375dfd0baecd9f1b7b06bb2d6f88d7cb8632"},{"url":"https://git.kernel.org/stable/c/0a04c0cb8606ff88399489d03ef255afe90d0d5f"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T13:24:55.520Z","slug":"CVE-2026-99066","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ncan: dev: init_can_skb(): restore skb header initialization\n\nCommit 9f10374bb024 (\"can: remove private CAN skb headroom infrastructure\")\nremoved the skb_reset_mac_header()/skb_reset_network_header()/\nskb_reset_transport_header() calls from init_can_skb(). As a result, RX\nskbs from alloc_can_skb() and friends again carry mac_header = 0xFFFF.\nWhen such an skb reaches packet_rcv_spkt() (SOCK_PACKET), the push length\ncalculation overflows and triggers skb_under_panic -> kernel BUG -> full\nmachine panic.\n\nThe same issue was originally reported in 2014 on linux-can and fixed by\ncommit 969439016d2c (\"can: add missing initialisations in CAN related\nskbuffs\"). packet_rcv_spkt() itself has never been hardened: only\npacket_rcv() and tpacket_rcv() gained dev_has_header() checks in\ncommit d549699048b4 (\"net/packet: fix packet receive on L3 devices\nwithout visible hard header\").\n\n## Affected\n\n- `Linux >= 9f10374bb024593a611e6845847f0444841a231b < 8078375dfd0baecd9f1b7b06bb2d6f88d7cb8632`\n- `Linux >= 9f10374bb024593a611e6845847f0444841a231b < 0a04c0cb8606ff88399489d03ef255afe90d0d5f`\n- `Linux 7.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}