{"cve":"CVE-2021-47293","nvd":{"published":"2024-05-21T15:15:17.243","modified":"2026-06-17T04:17:07.313","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b","https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d","https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6","https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024","https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47293","score":0.00234,"percentile":0.14363,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}