CVE-2026-98011
In the Linux kernel, the following vulnerability has been resolved: net/sched: hhf: clamp quantum in change and init paths hhf_change() accepts any quantum from userspace, including 1. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times under the qdisc lock (a soft lockup / denial of service). Add max(256U, ...) in hhf_change() matching fq_codel_change(). Clamp hhf_init() to [256, 1<<20] matching the siblings, and remove the old fallback that only set quantum=256 on overflow. Conditions to recreate the bug: CONFIG_NET_SCH_HHF=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root hhf tc qdisc change dev dummy0 root hhf quantum 1 stab data 32768 size_log 15 cell_log 0
- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-25)
- Published
- Modified
- Record from
- the NVD, synced
References
- https://git.kernel.org/stable/c/0898c6f9fa9ce2632ae88bd0f34a878ccc6335af
- https://git.kernel.org/stable/c/1113b674307ffddd402524bd1fd9d7d5629b705b
- https://git.kernel.org/stable/c/2c6dd9fc86d446a03728c43f3b96d9ae29aa058f
- https://git.kernel.org/stable/c/2e77947bbf6c166e76c038663832d0914418f761
- https://git.kernel.org/stable/c/6570f326a6a96bedf3d1d1dab6acc9f8c29104ec