CVE-2026-98013

In the Linux kernel, the following vulnerability has been resolved: net/sched: fq_pie: clamp quantum in change path fq_pie_change() accepts any quantum value 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, ...) matching fq_codel_change(). Conditions to recreate the bug: CONFIG_NET_SCH_FQ_PIE=y. Requires CAP_NET_ADMIN (namespace-local via unshare -Urn suffices). tc qdisc add dev dummy0 root fq_pie tc qdisc change dev dummy0 root fq_pie quantum 1 stab data 32768 size_log 15 cell_log 0

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

Frequently asked questions

  • What is CVE-2026-98013?

    CVE-2026-98013 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-2026-98013 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2026-98013?

    Yes. CVE-2026-98013 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-2026-98013 actively exploited?

    No. CVE-2026-98013 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.