CVE-2026-72392

/// Technical description

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

ipv6: fib6: fix NULL deref in fib6_walk_continue() on multi-batch dump

inet6_dump_fib() saves its progress in cb->args[1] as a positional

index within the current hash chain. Between batches, a concurrent

fib6_new_table() can insert a new table at the chain head, shifting

all existing entries. The saved index then lands on a different

table, causing fib6_dump_table() to set w->root to the wrong table

while w->node still points into the previous one.

fib6_walk_continue() dereferences w->node->parent (NULL) and panics:

BUG: kernel NULL pointer dereference, address: 0000000000000008

RIP: 0010:fib6_walk_continue+0x6e/0x170

Call Trace:

<TASK>

fib6_dump_table.isra.0+0xc5/0x240

inet6_dump_fib+0xf6/0x420

rtnl_dumpit+0x30/0xa0

netlink_dump+0x15b/0x460

netlink_recvmsg+0x1d6/0x2a0

____sys_recvmsg+0x17a/0x190

Fix by storing tb->tb6_id in cb->args[1] instead of a positional

index. On resume, skip e

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References