{"id":"CVE-2026-53014","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-53014","generatedAt":"2026-10-28T02:55:37.215Z","title":"In the Linux kernel, the following vulnerability has been resolved: net/sched: act_mirred: fix wrong device for mac_header_xmit check in tcf_blockcast_redir In tcf_blockcast_redir(), when iterating block ports to redirect packets to multiple devices,…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_mirred: fix wrong device for mac_header_xmit check in tcf_blockcast_redir\n\nIn tcf_blockcast_redir(), when iterating block ports to redirect\npackets to multiple devices, the mac_header_xmit flag is queried\nfrom the wrong device. The loop sends to dev_prev but queries\ndev_is_mac_header_xmit(dev) — which is the NEXT device in the\niteration, not the one being sent to.\n\nThis causes tcf_mirred_to_dev() to make incorrect decisions about\nwhether to push or pull the MAC header. When the block contains\nmixed device types (e.g., an ethernet veth and a tunnel device),\nintermediate devices get the wrong mac_header_xmit flag, leading to\nskb header corruption. In the worst case, skb_push_rcsum with an\nincorrect mac_len can exhaust headroom and panic.\n\nThe last device in the loop is handled correctly (line 365-366 uses\ndev_is_mac_header_xmit(dev_prev)), confirming this is a copy-paste\noversight for the intermediate devices.\n\nFix by using dev_prev instead of dev for the mac_header_xmit query,\nconsistent with the device actually being sent to.","published":"2026-06-24T17:17:13.000Z","lastModified":"2026-07-15T13:55:35.000Z","status":"Analyzed","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":[],"affected":["linux/linux kernel"],"epss":{"score":0.00162,"percentile":0.05313,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/4510d140524ca7d6e772db962e013f26f09a63b1","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4764953c4b47585eb72797b216b63a831dc0c7e6","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7db3e4e03032261b1b519341123fc30d995478ca","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8fda5174286119addd28473fb2ec5bdf521c05a8","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53014","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}