CVE-2026-31421

In the Linux kernel, the following vulnerability has been resolved: net/sched: clsfw: fix NULL pointer dereference on shared blocks The old-method path in fwclassify calls tcfblockq and dereferences q-handle. Shared blocks leave block-q NULL, causing a NULL deref when an empty clsfw filter is...

CVE-2026-31421

CVE-2026-31421 – Linux kernel net/sched cls_fw NULL pointer dereference . Root cause: in fw_classify(), the old-method path uses tcf_block_q() and dereferences q->handle; for shared blocks, block->q is NULL, causing a NULL pointer dereference when a nonzero skb is classified. The fix preven...