CVE-2026-72392
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 entries until the id matches; a concurrent head-insert can never match the saved id, so the walker always resumes on the correct table.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/059efb48dd746518898faaa9b965511009b59639
- https://git.kernel.org/stable/c/110ccbd28c9444866fcc84ba96a2ad64fa6e95ae
- https://git.kernel.org/stable/c/27210d433a8c5fe6bf7278a04bbaeb49a81d0290
- https://git.kernel.org/stable/c/89f9c5fee3c64c5cabc34e65599308fd3c879cf9
- https://git.kernel.org/stable/c/9facb861dc6b9b9ea9793ef5032a9a826f7a4229
- https://git.kernel.org/stable/c/d8a01d27873e04bebd357dc87859aa756e0b28b2
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.