{"id":"CVE-2026-72057","summary":"net/sched: act_ct: preserve tc_skb_cb across defragmentation","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_ct: preserve tc_skb_cb across defragmentation\n\ntcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving\nand restoring skb-\u003ecb. The defrag helper clears IPCB/IP6CB, which aliases\nthe tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through\nact_ct therefore loses qdisc metadata such as pkt_segs and can trigger\nWARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled.\n\nSave and restore the full tc_skb_cb around nf_ct_handle_fragments(),\nmatching the pattern used by ovs_ct_handle_fragments().","modified":"2026-08-25T03:51:53.608444491Z","published":"2026-08-15T05:52:12.873Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72057.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2400c4b05d58834b994500a9eec90a37db44187c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac"},{"type":"WEB","url":"https://git.kernel.org/stable/c/67d6b00a54446c008f52cf70fc0c2ad0c712f85d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9092e15defbe6c7bc241c306093ca9d358a578e7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b3d835407846134b0d54637c0281b39bebef831d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f7f45ceb855d9ba1cba594fb3f383255f7013fad"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fb080b6f54835d5d4d11ce3122800e6f0f6689e6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72057.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72057"},{"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":"0d76daf2013ce1da20eab5e26bd81d983e1c18fb"},{"fixed":"fb080b6f54835d5d4d11ce3122800e6f0f6689e6"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"ec624fe740b416fb68d536b37fb8eef46f90b5c2"},{"fixed":"67d6b00a54446c008f52cf70fc0c2ad0c712f85d"},{"fixed":"2400c4b05d58834b994500a9eec90a37db44187c"},{"fixed":"5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac"},{"fixed":"b3d835407846134b0d54637c0281b39bebef831d"},{"fixed":"f7f45ceb855d9ba1cba594fb3f383255f7013fad"},{"fixed":"9092e15defbe6c7bc241c306093ca9d358a578e7"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.15.13"},{"fixed":"5.15.217"}]}],"versions":["v5.15.216","v5.15.215","v5.15.214","v5.15.213","v5.15.212","v5.15.211","v5.15.210","v5.15.209","v5.15.208","v5.15.207","v5.15.206","v5.15.205","v5.15.204","v5.15.203","v5.15.202","v5.15.201","v5.15.200","v5.15.199","v5.15.198","v5.15.197","v5.15.196","v5.15.195","v5.15.194","v5.15.193","v5.15.192","v5.15.191","v5.15.190","v5.15.189","v5.15.188","v5.15.187","v5.15.186","v5.15.185","v5.15.184","v5.15.183","v5.15.182","v5.15.181","v5.15.180","v5.15.179","v5.15.178","v5.15.177","v5.15.176","v5.15.175","v5.15.174","v5.15.173","v5.15.172","v5.15.171","v5.15.170","v5.15.169","v5.15.168","v5.15.167","v5.15.166","v5.15.165","v5.15.164","v5.15.163","v5.15.162","v5.15.161","v5.15.160","v5.15.159","v5.15.158","v5.15.157","v5.15.156","v5.15.155","v5.15.154","v5.15.153","v5.15.152","v5.15.151","v5.15.150","v5.15.149","v5.15.148","v5.15.147","v5.15.146","v5.15.145","v5.15.144","v5.15.143","v5.15.142","v5.15.141","v5.15.140","v5.15.139","v5.15.138","v5.15.137","v5.15.136","v5.15.135","v5.15.134","v5.15.133","v5.15.132","v5.15.131","v5.15.130","v5.15.129","v5.15.128","v5.15.127","v5.15.126","v5.15.125","v5.15.124","v5.15.123","v5.15.122","v5.15.121","v5.15.120","v5.15.119","v5.15.118","v5.15.117","v5.15.116","v5.15.115","v5.15.114","v5.15.113","v5.15.112","v5.15.111","v5.15.110","v5.15.109","v5.15.108","v5.15.107","v5.15.106","v5.15.105","v5.15.104","v5.15.103","v5.15.102","v5.15.101","v5.15.100","v5.15.99","v5.15.98","v5.15.97","v5.15.96","v5.15.95","v5.15.94","v5.15.93","v5.15.92","v5.15.91","v5.15.90","v5.15.89","v5.15.88","v5.15.87","v5.15.86","v5.15.85","v5.15.84","v5.15.83","v5.15.82","v5.15.81","v5.15.80","v5.15.79","v5.15.78","v5.15.77","v5.15.76","v5.15.75","v5.15.74","v5.15.73","v5.15.72","v5.15.71","v5.15.70","v5.15.69","v5.15.68","v5.15.67","v5.15.66","v5.15.65","v5.15.64","v5.15.63","v5.15.62","v5.15.61","v5.15.60","v5.15.59","v5.15.58","v5.15.57","v5.15.56","v5.15.55","v5.15.54","v5.15.53","v5.15.52","v5.15.51","v5.15.50","v5.15.49","v5.15.48","v5.15.47","v5.15.46","v5.15.45","v5.15.44","v5.15.43","v5.15.42","v5.15.41","v5.15.40","v5.15.39","v5.15.38","v5.15.37","v5.15.36","v5.15.35","v5.15.34","v5.15.33","v5.15.32","v5.15.31","v5.15.30","v5.15.29","v5.15.28","v5.15.27","v5.15.26","v5.15.25","v5.15.24","v5.15.23","v5.15.22","v5.15.21","v5.15.20","v5.15.19","v5.15.18","v5.15.17","v5.15.16","v5.15.15","v5.15.14","v5.15.13"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72057.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.217"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.184"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.12.97"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced"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