CVE-2026-98567 json
net: xps: reject an out of range traffic class
published 24d ago modified 23d ago also EUVD-2026-103612
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
net: xps: reject an out of range traffic class
Only the entries below dev->num_tc are valid in dev->tc_to_txq[], and dev->prio_tc_map[] may only name classes below it. netdev_set_num_tc() lowers dev->num_tc without touching either array.
netdev_txq_to_tc() walks all TC_MAX_QUEUE slots and netdev_get_prio_tc_map() returns the entry as it stands, so a leftover entry is handed out as a traffic class >= dev->num_tc. Taking that class from netdev_txq_to_tc(), __netif_set_xps_queue() rejects only a negative one and indexes an XPS map sized for dev->num_tc classes:
tci = j * num_tc + tc; RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
attr_map[] holds nr_ids * num_tc entries and j runs over the ids named in the mask, so a class that is not below num_tc pushes tci past the end of the map for the last ids and the store overruns it.
Any caller that lowers num_tc leaves such entries behind, and mqprio_destroy() tears down with netdev_set_num_tc(dev, 0) rather than netdev_reset_tc(). After mqprio with 8 classes then 1, tc_to_txq[1..7] still describe txq 1..7. The splat is from an XPS write to txq 2 on a veth with 8 rx queues: attr_map[] has 8 * 1 entries, tci = j + 2, and j == 6 stores one past the end of the 88-byte map:
BUG: KASAN: slab-out-of-bounds in __netif_set_xps_queue (net/core/dev.c:2954) Write of size 8 at addr ffff88813016bc58 by task xps_oob/634 __netif_set_xps_queue (net/core/dev.c:2954) xps_rxqs_store (net/core/net-sysfs.c:1880) netdev_queue_attr_store (net/core/net-sysfs.c:1390) Allocated by task 634: __kmalloc_noprof (mm/slub.c:5439) __netif_set_xps_queue (net/core/dev.c:2937) The buggy address is located 0 bytes to the right of allocated 88-byte region [ffff88813016bc00, ffff88813016bc58)
Reject a class the map has no room for.
Patch / fix
- Linux Linux 7.3
- linux Debian 12 6.1.190-1
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.9-1
- linux-6.12 Debian 12 6.12.113-1~deb12u1
debian advisories DEBIAN-CVE-2026-98567
- linux Ubuntu 22.04 LTS 5.15.0-202.212
- linux Ubuntu 24.04 LTS 6.8.0-149.149
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 22.04 LTS 5.15.0-1119.126
- linux-aws Ubuntu 24.04 LTS 6.8.0-1069.74
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 22.04 LTS 5.15.0-1120.130
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1073.81
ubuntu advisories UBUNTU-CVE-2026-98567
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel Azure Linux 3.0 6.6.159.1-1
azure linux advisories AZL-108792
Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT
- git.kernel.org/stable/c/967e10f40a0c6732db299cbe001df0e859196055 commit
- git.kernel.org/stable/c/1cb8e40525a72c9f1e1cf94c68c172b3b9bbdc81 commit
- git.kernel.org/stable/c/6ea8f643053f33622f9116e4e1db58306ece45e3 commit
- git.kernel.org/stable/c/9e841723ba482d41ecbf90241c756a16cdfea949 commit
- git.kernel.org/stable/c/eff227a3cb4d0089fbb85c73480bf8abf2e5ae7f commit
- git.kernel.org/stable/c/2cc1c3977acbffc417fb5b57699d1df3dcffb5fd commit
- git.kernel.org/stable/c/930318290d8509e864c015fe6c9239470b3c579c commit
- git.kernel.org/stable/c/4da3b7b8b50f3e2fde54a4c18a82a8e3f6223910 commit
Is CVE-2026-98567 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-98567 updated cvss 5.5
kernel: net: xps: reject an out of range traffic class
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: no fix planned “Out of support scope”
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Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9affected: no fix available “Fix deferred”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/967e10f40a0c6732db299cbe001df0e859196055
- git.kernel.org /stable/c/1cb8e40525a72c9f1e1cf94c68c172b3b9bbdc81
- git.kernel.org /stable/c/6ea8f643053f33622f9116e4e1db58306ece45e3
- git.kernel.org /stable/c/9e841723ba482d41ecbf90241c756a16cdfea949
- git.kernel.org /stable/c/eff227a3cb4d0089fbb85c73480bf8abf2e5ae7f
- git.kernel.org /stable/c/2cc1c3977acbffc417fb5b57699d1df3dcffb5fd
- git.kernel.org /stable/c/930318290d8509e864c015fe6c9239470b3c579c
- git.kernel.org /stable/c/4da3b7b8b50f3e2fde54a4c18a82a8e3f6223910
Sources
- CVE List CVE-2026-98567
- NVD CVE-2026-98567
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