{"id":"CVE-2026-53014","summary":"net/sched: act_mirred: fix wrong device for mac_header_xmit check in tcf_blockcast_redir","details":"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.","modified":"2026-07-17T03:31:44.097837434Z","published":"2026-06-24T16:29:24.605Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53014.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/4510d140524ca7d6e772db962e013f26f09a63b1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4764953c4b47585eb72797b216b63a831dc0c7e6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7db3e4e03032261b1b519341123fc30d995478ca"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8fda5174286119addd28473fb2ec5bdf521c05a8"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53014.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53014"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"42f39036cda808d3de243192a2cf5125f12f3047"},{"fixed":"8fda5174286119addd28473fb2ec5bdf521c05a8"},{"fixed":"7db3e4e03032261b1b519341123fc30d995478ca"},{"fixed":"4764953c4b47585eb72797b216b63a831dc0c7e6"},{"fixed":"4510d140524ca7d6e772db962e013f26f09a63b1"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-53014.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.12.91"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.33"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-53014.json"}}],"schema_version":"1.7.5"}