CVE-2026-98301 json
net: bridge: mst: move switchdev call outside rcu
published last mo. modified 23d ago also EUVD-2026-93286
- 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 7%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mst: move switchdev call outside rcu
This is a follow-up of one of sashiko's pre-existing bug reports. br_mst_set_state() calls switchdev_port_attr_set() for nonzero MSTIs while holding rcu_read_lock() which invokes the blocking switchdev notifier chain and may sleep. Nonzero MSTI changes come from netlink with rtnl held. Move the switchdev call before entering the rcu section and assert that rtnl is held.
The call cannot be deferred because netlink needs its error and extack. Also DSA reads the old bridge MST state during the callback and checks it. A deferred callback will be late and will see the updated state.
Patch / fix
- Linux Linux 6.1.189, 6.6.158, 6.9, 6.10, 7.3
- linux Debian 12 6.1.190-1
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.8-1
- linux-6.12 Debian 12 6.12.113-1~deb12u1
debian advisories DEBIAN-CVE-2026-98301
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
- linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
- linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
- linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
- linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
- linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17
ubuntu advisories UBUNTU-CVE-2026-98301
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-source openSUSE Tumbleweed 7.2.10-1.1
opensuse advisories openSUSE-SU-2026:12131-1
- git.kernel.org/stable/c/b9661fd2423fc25e91e0517ecc0b6156ad83e3a8 commit
- git.kernel.org/stable/c/6b431b63219853eef4054e2f1cb073d2ca2059b4 commit
- git.kernel.org/stable/c/abf734d150c61acfdfee102169d0e5d1c482e285 commit
- git.kernel.org/stable/c/d5c4ee1fa4e83a12afc051c831936cd8e006cde3 commit
- git.kernel.org/stable/c/c40ed3e884c8dc0350f26484030438ef24208ff1 commit
- git.kernel.org/stable/c/18a6fe05fb6e18de29fa90d388bb34044114b3d8 commit
Is CVE-2026-98301 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-2026-98301 updated cvss 4.7
kernel: net: bridge: mst: move switchdev call outside rcu
-
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-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9affected: workaround, no fix available “Fix deferred”
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Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8not affected: vulnerable code not present
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
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/b9661fd2423fc25e91e0517ecc0b6156ad83e3a8
- git.kernel.org /stable/c/6b431b63219853eef4054e2f1cb073d2ca2059b4
- git.kernel.org /stable/c/abf734d150c61acfdfee102169d0e5d1c482e285
- git.kernel.org /stable/c/d5c4ee1fa4e83a12afc051c831936cd8e006cde3
- git.kernel.org /stable/c/c40ed3e884c8dc0350f26484030438ef24208ff1
- git.kernel.org /stable/c/18a6fe05fb6e18de29fa90d388bb34044114b3d8
Sources
- CVE List CVE-2026-98301
- NVD CVE-2026-98301
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.