IT

Tracker / CVE-2026-31422

CVE-2026-31422

Medium 5.5

In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: fix NULL pointer dereference on shared blocks flow_change() calls tcf_block_q() and dereferences q->handle to derive a default baseclass. Shared blocks leave block->q NULL, causing a NULL deref when a flow filter without a fully qualified baseclass is created on a shared block. Check tcf_block_shared() before accessing block->q and return -EINVAL for shared blocks. This avoids the null-deref shown below: ======================================================================= KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] RIP: 0010:flow_change (net/sched/cls_flow.c:508) Call Trace: tc_new_tfilter (net/sched/cls_api.c:2432) rtnetlink_rcv_msg (net/core/rtnetlink.c:6980) [...] =======================================================================

Affected products and versions

linux linux_kernel
linux linux_kernel · 4.15 → 5.10.253
linux linux_kernel · 5.11 → 5.15.203
linux linux_kernel · 5.16 → 6.1.168
linux linux_kernel · 6.13 → 6.18.22
linux linux_kernel · 6.19 → 6.19.12
linux linux_kernel · 6.2 → 6.6.134
linux linux_kernel · 6.7 → 6.12.81

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References