CVE-2026-98027 json
net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size
published last mo. modified 24d ago also EUVD-2026-86680
- cvss
- 7.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 1%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size
mv88e6xxx_get_rxnfc() uses rxnfc->rule_cnt as the write index while dumping the policy IDR, clobbering the input value before it has been looked at. That input is the number of entries the caller had room for. ETHTOOL_GRXCLSRLALL requires no CAP_NET_ADMIN and the ioctl sizes the buffer from the rule_cnt userspace passes in, so once an admin has installed policy rules any user can ask for fewer slots than there are rules and run off the end of the allocation. A rule_cnt of 0 leaves the buffer pointer NULL and the walk dereferences it.
Count into a local so the caller's limit survives the walk, and stop with -EMSGSIZE once it is reached.
Patch / fix
- Linux Linux 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53, 7.2.7, 7.3
- linux Debian 12 6.1.190-1
- linux Debian 13 6.12.111-1
- linux Debian 14 7.2.7-1
- linux-6.12 Debian 12 6.12.111-1~deb12u1
debian advisories DEBIAN-CVE-2026-98027
- 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-2026-98027
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 7.2.9-1.1
opensuse advisories openSUSE-SU-2026:12074-1
- kernel Azure Linux 3.0 6.6.158.1-1
azure linux advisories AZL-104448
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/7e4bfc5f0b66feb22cba821303fc25ca22cd0887 commit
- git.kernel.org/stable/c/01124cd2cf4b71755b1130ac82d78dcfbd5d69e3 commit
- git.kernel.org/stable/c/609c4378f212cf580aae02250f1146caf63d873f commit
- git.kernel.org/stable/c/c5b5c52b6524c9fb50def2260baac745c095ec3a commit
- git.kernel.org/stable/c/44cd4674d9aa5bdf793b8a8b481c9e8536ed6070 commit
- git.kernel.org/stable/c/7a683c2b062810bca203e41866389daf387c235b commit
- git.kernel.org/stable/c/cda5ac8fe8ac8e80b1703ebb8c4250726fc19739 commit
- git.kernel.org/stable/c/b1fffc273112e7284c5b705e186b43b5770cd3d5 commit
Is CVE-2026-98027 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-2026-98027 updated cvss 5.5
kernel: net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size
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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 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-9not affected: vulnerable code not present
+1 more productsfewer
Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
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
0.12% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/7e4bfc5f0b66feb22cba821303fc25ca22cd0887
- git.kernel.org /stable/c/01124cd2cf4b71755b1130ac82d78dcfbd5d69e3
- git.kernel.org /stable/c/609c4378f212cf580aae02250f1146caf63d873f
- git.kernel.org /stable/c/c5b5c52b6524c9fb50def2260baac745c095ec3a
- git.kernel.org /stable/c/44cd4674d9aa5bdf793b8a8b481c9e8536ed6070
- git.kernel.org /stable/c/7a683c2b062810bca203e41866389daf387c235b
- git.kernel.org /stable/c/cda5ac8fe8ac8e80b1703ebb8c4250726fc19739
- git.kernel.org /stable/c/b1fffc273112e7284c5b705e186b43b5770cd3d5
Sources
- CVE List CVE-2026-98027
- NVD CVE-2026-98027
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