CVE-2026-72057

Summary

In the Linux kernel, the following vulnerability has been resolved:

net/sched: act_ct: preserve tc_skb_cb across defragmentation

tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled.

Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments().

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxec624fe740b416fb68d536b37fb8eef46f90b5c2 < 2400c4b05d58834b994500a9eec90a37db44187caffected
LinuxLinuxec624fe740b416fb68d536b37fb8eef46f90b5c2 < 5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bacaffected
LinuxLinuxec624fe740b416fb68d536b37fb8eef46f90b5c2 < b3d835407846134b0d54637c0281b39bebef831daffected
LinuxLinuxec624fe740b416fb68d536b37fb8eef46f90b5c2 < f7f45ceb855d9ba1cba594fb3f383255f7013fadaffected
LinuxLinuxec624fe740b416fb68d536b37fb8eef46f90b5c2 < 9092e15defbe6c7bc241c306093ca9d358a578e7affected
LinuxLinux0d76daf2013ce1da20eab5e26bd81d983e1c18fbaffected
LinuxLinux5.15.13 < 5.16affected
LinuxLinux5.16affected
LinuxLinux0 < 5.16unaffected
LinuxLinux6.6.145 <= 6.6.*unaffected
LinuxLinux6.12.97 <= 6.12.*unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References