What is CVE-2026-98009?

CVE-2026-98009 is a unscored severity Linux kernel vulnerability, affecting Linux kernel versions from 5.6 onward and patched in 5.10.271, 5.15.222, 6.1.189 and others. CVE-2026-98009 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-98009?

CVE-2026-98009 has a CVSS score of pending NVD analysis out of 10, rated awaiting scoring severity.

Is there a patch available for CVE-2026-98009?

Yes, CVE-2026-98009 has been patched. Fixed versions include 5.10.271, 5.15.222, 6.1.189 and others. If you are running Linux kernel 5.6 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-98009 actively exploited?

CVE-2026-98009 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-98009

In the Linux kernel, the following vulnerability has been resolved: net/sched: ets: clamp quantum in parse and fallback paths ets_qdisc_change() falls back to psched_mtu() with no floor for bands without an explicit quantum. With a crafted size table qdisc_pkt_len reaches ~2 GiB, so a zero psched_mtu on a headerless device makes the deficit-refill loop spin under the qdisc lock. Move the floor into ets_quantum_parse() so explicitly configured quanta are also clamped to [256, 1<<20], not just the fallback path. Conditions to recreate the bug: CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1

Package Linux Kernel

Published 2026-09-25

Last modified 2026-10-03

Patch available

Yes

Affected versions

Linux kernel versions 5.6 and later are affected. Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7, 7.3-rc3 and their respective stable series.

Affected from

≥ 5.6

Fixed in

✓ 5.10.271 5.10.x ✓ 5.15.222 5.15.x ✓ 6.1.189 6.1.x ✓ 6.6.158 6.6.x ✓ 6.12.111 6.12.x ✓ 6.18.53 6.18.x ✓ 7.2.7 7.2.x ✓ 7.3-rc3

References

8 total

Showing 5 of 8 references View all on NVD

Frequently asked questions

What is CVE-2026-98009?

CVE-2026-98009 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.6 onward and has been patched in 5.10.271, 5.15.222, 6.1.189 and others. CVE-2026-98009 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
Is there a patch available for CVE-2026-98009?

Yes. CVE-2026-98009 has been patched. Fixed versions include 5.10.271, 5.15.222, 6.1.189 and others. If you are running Linux kernel 5.6 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-98009 actively exploited?

No. CVE-2026-98009 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.