{"id":"CVE-2021-47293","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_skbmod: Skip non-Ethernet packets\n\nCurrently tcf_skbmod_act() assumes that packets use Ethernet as their L2\nprotocol, which is not always the case.  As an example, for CAN devices:\n\n\t$ ip link add dev vcan0 type vcan\n\t$ ip link set up vcan0\n\t$ tc qdisc add dev vcan0 root handle 1: htb\n\t$ tc filter add dev vcan0 parent 1: protocol ip prio 10 \\\n\t\tmatchall action skbmod swap mac\n\nDoing the above silently corrupts all the packets.  Do not perform skbmod\nactions for non-Ethernet packets.","modified":"2026-03-15T22:42:47.829707Z","published":"2024-05-21T15:15:17.243Z","related":["SUSE-SU-2024:2360-1","SUSE-SU-2024:2381-1","SUSE-SU-2024:2561-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d"},{"type":"FIX","url":"https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6"},{"type":"FIX","url":"https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024"},{"type":"FIX","url":"https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c"},{"type":"FIX","url":"https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b"}],"affected":[{"database_specific":{"unresolved_ranges":[{"events":[{"introduced":"4.9"},{"fixed":"4.19.199"}]},{"events":[{"introduced":"4.20"},{"fixed":"5.4.136"}]},{"events":[{"introduced":"5.5"},{"fixed":"5.10.54"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.13.6"}]},{"events":[{"introduced":"0"},{"last_affected":"5.14-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.14-rc2"}]}],"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47293.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}