UBUNTU-CVE-2025-38509: Medium severity ubuntu/linux-hwe-edge vulnerability

Q: What conditions are required to trigger the issue?

An attacker needs local, low-privileged access and must be able to supply a malformed VHT operating mode notification using an unsupported 5 MHz or 10 MHz channel width. The vulnerable path is used when opmode_notif is processed.

Q: What is the practical impact of successful triggering?

Malformed input can reach ieee80211_chan_width_to_rx_bw() with an invalid channel width and cause a WARN_ON. The provided severity vector indicates availability impact only, with no stated impact on confidentiality or integrity.

Q: Which channel widths are invalid for VHT notifications?

VHT operating mode notifications must reject 5 MHz and 10 MHz widths. Valid VHT widths are 20, 40, 80, 160, and 80+80 MHz; 320 MHz is also permitted by the fix to avoid rejecting HE or EHT clients that send a VHT opmode notification.

Q: Which Ubuntu kernel packages are listed as affected?

The listed packages are ubuntu/linux-riscv, ubuntu/linux-hwe-edge, ubuntu/linux-azure-fde, ubuntu/linux-realtime, ubuntu/linux-aws-5.0, ubuntu/linux-aws-5.3, ubuntu/linux-azure, and ubuntu/linux-azure-5.3.

Published Aug 16, 2025

Updated

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reject VHT opmode for unsupported channel widths VHT operating mode notifications are not defined for channel widths below 20 MHz. In particular, 5 MHz and 10 MHz are not valid under the VHT specification and must be rejected. Without this check, malformed notifications using these widths may reach ieee80211chanwidthtorxbw(), leading to a WARNON due to invalid input. This issue was reported by syzbot. Reject these unsupported widths early in stalinkapplyparameters() when opmodenotif is used. The accepted set includes 20, 40, 80, 160, and 80+80 MHz, which are valid for VHT. While 320 MHz is not defined for VHT, it is allowed to avoid rejecting HE or EHT clients that may still send a VHT opmode notification.

Affected Software

97 affected componentsFixes available

ubuntu/linux-hwe-edge*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-azure*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-oem*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

ubuntu/linux-gkeop*

ubuntu/linux-gkeop-5.15*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.8*

ubuntu/linux-intel-5.13*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle-6.5*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-aws-6.14<6.14.0-1017.17~24.04.1

6.14.0-1017.17~24.04.1

ubuntu/linux-azure-6.11*

ubuntu/linux-azure-6.14<6.14.0-1017.17~24.04.1

6.14.0-1017.17~24.04.1

ubuntu/linux-azure-fde-6.14*

ubuntu/linux-azure-nvidia-6.14*

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14<6.14.0-1020.21~24.04.1

6.14.0-1020.21~24.04.1

ubuntu/linux-hwe-6.11*

ubuntu/linux-intel*

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-oem-6.14<6.14.0-1016.16

6.14.0-1016.16

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle-6.14<6.14.0-1017.17~24.04.1

6.14.0-1017.17~24.04.1

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-6.14<6.14.0-36.36.1~24.04.1

6.14.0-36.36.1~24.04.1

ubuntu/linux-realtime-6.14<6.14.0-1016.16~24.04.1

6.14.0-1016.16~24.04.1

ubuntu/linux-azure-fde*

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1017.17~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1017.17~24.04.1
Upgrade
Upgrade ubuntu/linux-gcp-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1020.21~24.04.1
Upgrade
Upgrade ubuntu/linux-oem-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1016.16
Upgrade
Upgrade ubuntu/linux-oracle-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1017.17~24.04.1
Upgrade
Upgrade ubuntu/linux-riscv-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-36.36.1~24.04.1
Upgrade
Upgrade ubuntu/linux-realtime-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1016.16~24.04.1
Compensating control
In sta_link_apply_parameters(), reject VHT operating-mode notifications for channel widths below 20 MHz, including 5 MHz and 10 MHz; accept 20, 40, 80, 160, and 80+80 MHz, while allowing 320 MHz to avoid rejecting HE or EHT clients.

Event History

Aug 16, 2025

CVE Published

via OSV·11:15 AM

Data Sourced

via OSV·11:15 AM

DescriptionSeverityAffected Software

Frequently Asked Questions

What conditions are required to trigger the issue?

An attacker needs local, low-privileged access and must be able to supply a malformed VHT operating mode notification using an unsupported 5 MHz or 10 MHz channel width. The vulnerable path is used when opmode_notif is processed.

What is the practical impact of successful triggering?

Malformed input can reach ieee80211_chan_width_to_rx_bw() with an invalid channel width and cause a WARN_ON. The provided severity vector indicates availability impact only, with no stated impact on confidentiality or integrity.

Which channel widths are invalid for VHT notifications?

VHT operating mode notifications must reject 5 MHz and 10 MHz widths. Valid VHT widths are 20, 40, 80, 160, and 80+80 MHz; 320 MHz is also permitted by the fix to avoid rejecting HE or EHT clients that send a VHT opmode notification.

Which Ubuntu kernel packages are listed as affected?

The listed packages are ubuntu/linux-riscv, ubuntu/linux-hwe-edge, ubuntu/linux-azure-fde, ubuntu/linux-realtime, ubuntu/linux-aws-5.0, ubuntu/linux-aws-5.3, ubuntu/linux-azure, and ubuntu/linux-azure-5.3.

UBUNTU-CVE-2025-38509: Medium severity ubuntu/linux-hwe-edge vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

What conditions are required to trigger the issue?

What is the practical impact of successful triggering?

Which channel widths are invalid for VHT notifications?

Which Ubuntu kernel packages are listed as affected?

Company

Resources

Contact

Frequently Asked Questions

What conditions are required to trigger the issue?

What is the practical impact of successful triggering?

Which channel widths are invalid for VHT notifications?

Which Ubuntu kernel packages are listed as affected?