CVE-2025-68795

Linux kernel (Azure) vulnerabilities

Description

In the Linux kernel, the following vulnerability has been resolved:

ethtool: Avoid overflowing userspace buffer on stats query

The ethtool -S command operates across three ioctl calls: ETHTOOL_GSSET_INFO for the size, ETHTOOL_GSTRINGS for the names, and ETHTOOL_GSTATS for the values.

If the number of stats changes between these calls (e.g., due to device reconfiguration), userspace's buffer allocation will be incorrect, potentially leading to buffer overflow.

Drivers are generally expected to maintain stable stat counts, but some drivers (e.g., mlx5, bnx2x, bna, ksz884x) use dynamic counters, making this scenario possible.

Some drivers try to handle this internally:

  • bnad_get_ethtool_stats() returns early in case stats.n_stats is not equal to the driver's stats count.
  • micrel/ksz884x also makes sure not to write anything beyond stats.n_stats and overflow the buffer.

However, both use stats.n_stats which is already assigned with the value returned from get_sset_count(), hence won't solve the issue described here.

Change ethtool_get_strings(), ethtool_get_stats(), ethtool_get_phy_stats() to not return anything in case of a mismatch between userspace's size and get_sset_size(), to prevent buffer overflow. The returned n_stats value will be equal to zero, to reflect that nothing has been returned.

This could result in one of two cases when using upstream ethtool, depending on when the size change is detected:

  1. When detected in ethtool_get_strings():

    ethtool -S eth2

    no stats available

  2. When detected in get stats, all stats will be reported as zero.

Both cases are presumably transient, and a subsequent ethtool call should succeed.

Other than the overflow avoidance, these two cases are very evident (no output/cleared stats), which is arguably better than presenting incorrect/shifted stats. I also considered returning an error instead of a "silent" response, but that seems more destructive towards userspace apps.

Notes:

  • This patch does not claim to fix the inherent race, it only makes sure that we do not overflow the userspace buffer, and makes for a more predictable behavior.

  • RTNL lock is held during each ioctl, the race window exists between the separate ioctl calls when the lock is released.

  • Userspace ethtool always fills stats.n_stats, but it is likely that these stats ioctls are implemented in other userspace applications which might not fill it. The added code checks that it's not zero, to prevent any regressions.

Metrics

Severity
high
no public PoC known
7.8
Source: nvd-v3
6.2 %
Low — this CVE sits in the lower 10% of all CVEs scored today.
0.2 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-06-16 22:30 UTC

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. CVE Modified2026-07-30 06:24 UTC· 416baaa9-dc9f-4396-8d5f-8c081fb06d67
    • CVSS V3.1: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected operating systems

  • linux

    amazon / amazon_linux

  • linux

    ubuntu / awsbionic

  • linux

    ubuntu / awsjammy

  • linux

    ubuntu / awsnoble

  • linux

    ubuntu / awsresolute

  • linux

    ubuntu / awsxenial

  • linux

    ubuntu / aws-6.8jammy

  • linux

    ubuntu / aws-hwexenial

  • linux

    ubuntu / azurejammy

  • linux

    ubuntu / azurenoble

  • linux

    ubuntu / azureresolute

  • linux

    ubuntu / azurexenial

  • linux

    ubuntu / azure-4.15bionic

  • linux

    suse / basesystem_module15

  • linux

    debian / debian_linux11.0

  • linux

    debian / debian_linux12.0

  • linux

    debian / debian_linux13.0

  • linux

    suse / development_tools_module15

  • linux

    redhat / enterprise_linux10.0

  • linux

    redhat / enterprise_linux8.0

  • linux

    redhat / enterprise_linux9.0

  • linux

    redhat / enterprise_linux_aus8.4

  • linux

    redhat / enterprise_linux_aus8.6

  • linux

    redhat / enterprise_linux_eus10.0

Affected products

Products and version ranges extracted from the vendor/CERT advisory. A range like „<4.14.6“ implies the update recommendation „upgrade to 4.14.6 or later“.

  • arista

    cloudvision_agni2024.4.0 – 2025.2.2

  • arista

    cloudvision_portal2024.2.0 – 2026.1.0

  • arista

    velocloud_edge4.5.0 – 6.4.1

  • arista

    velocloud_gateway

  • arista

    velocloud_orchestrator

  • IBM

    QRadar SIEM<7.5.0 UP15 IF06

  • redhat

    openshift_container_platform4.12 – 4.12.89

  • redhat

    openshift_container_platform4.13 – 4.13.66

  • redhat

    openshift_container_platform4.14 – 4.14.65

  • redhat

    openshift_container_platform4.15 – 4.15.64

  • redhat

    openshift_container_platform4.16 – 4.16.61

  • redhat

    openshift_container_platform4.17 – 4.17.53

  • redhat

    openshift_container_platform4.18 – 4.18.40

  • redhat

    openshift_container_platform4.19 – 4.19.30

  • redhat

    openshift_container_platform4.20 – 4.20.21

  • redhat

    openshift_container_platform4.21 – 4.21.14

  • redhat

    openshift_container_platform

  • siemens

    simatic_ax_runtime

  • suse

    caas_platform

  • suse

    enterprise_storage

  • suse

    manager_proxy

  • suse

    manager_retail_branch_server

  • suse

    manager_server

  • suse

    openstack_cloud

References & sources

Linked CVEs

Show 368 more CVEs
IDCVE-2025-68795