What is CVE-2026-46331?
In the Linux kernel, the following vulnerability has been resolved: net/sched: fix pedit partial COW leading to page cache corruption tcf_pedit_act() computes the COW range for skb_ensure_writable() once before the key loop using tcfp_off_max_hint, but the hint does not account for the runtime header offset added by typed keys. This can leave part of the write region un-COW'd. Fix by moving skb_ensure_writable() inside the per-key loop where the actual write offset is known, and add overflow checking on the offset arithmetic. For negative offsets (e.g. Ethernet header edits at ingress), use skb_cow() to COW the headroom instead. Guard offset_valid() against INT_MIN, where negation is undefined.
Affected product
Linux kernel (traffic-control subsystem, act_pedit)
Remediation Steps
- Apply kernel security patch from your Linux distribution vendor as soon as available
- Prioritize systems running untrusted or shared workloads where local users have shell access
- Monitor for privilege escalation attempts targeting the traffic-control subsystem
- Review system logs for unauthorized root-level process execution