In the Linux kernel, the following vulnerability has been resolved:
can: mcba_usb: populate ndo_change_mtu() to prevent buffer overflow
Sending an PF_PACKET allows to bypass the CAN framework logic and to directly reach the xmit() function of a CAN driver. The only check which is performed by the PF_PACKET framework is to make sure that skb->len fits the interface's MTU.
Unfortunately, because the mcba_usb driver does not populate its net_device_ops->ndo_change_mtu(), it is possible for an attacker to configure an invalid MTU by doing, for example:
$ ip link set can0 mtu 9999
After doing so, the attacker could open a PF_PACKET socket using the ETH_P_CANXL protocol:
socket(PF_PACKET, SOCK_RAW, htons(ETH_P_CANXL))
to inject a malicious CAN XL frames. For example:
struct canxl_frame frame = { .flags = 0xff, .len = 2048, };
The CAN drivers' xmit() function are calling can_dev_dropped_skb() to check that the skb is valid, unfortunately under above conditions, the malicious packet is able to go through can_dev_dropped_skb() checks:
1. the skb->protocol is set to ETH_P_CANXL which is valid (the function does not check the actual device capabilities).
2. the length is a valid CAN XL length.
And so, mcba_usb_start_xmit() receives a CAN XL frame which it is not able to correctly handle and will thus misinterpret it as a CAN frame.
This can result in a buffer overflow. The driver will consume cf->len as-is with no further checks on these lines:
usb_msg.dlc = cf->len;
memcpy(usb_msg.data, cf->data, usb_msg.dlc);
Here, cf->len corresponds to the flags field of the CAN XL frame. In our previous example, we set canxl_frame->flags to 0xff. Because the maximum expected length is 8, a buffer overflow of 247 bytes occurs!
Populate net_device_ops->ndo_change_mtu() to ensure that the interface's MTU can not be set to anything bigger than CAN_MTU. By fixing the root cause, this prevents the buffer overflow.
CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade linuxUpgrade linux-6.1 | Nov 13, 2025 | Nov 13, 2025 |
| Suse | — | Upgrade kernel-default-baseUpgrade kernel-64kbUpgrade kernel-macrosUpgrade kernel-default-develUpgrade reiserfs-kmp-defaultUpgrade kernel-zfcpdumpUpgrade kernel-obs-buildUpgrade kernel-64kb-develUpgrade kernel-sourceUpgrade kernel-defaultUpgrade kernel-docsUpgrade kernel-symsUpgrade kernel-develUpgrade kernel-default-extra | Dec 5, 2025 | Nov 11, 2025 |
| Ubuntu | — | Upgrade linux-image-generic-6.8Upgrade linux-image-5.15.0-1096-gkeUpgrade linux-image-intel-iotg-5.15Upgrade linux-image-aws-64k-lts-22.04Upgrade linux-image-aws-64k-6.8Upgrade linux-image-6.8.0-1052-gcp-64kUpgrade linux-image-6.8.0-1049-ibmUpgrade linux-image-oem-20.04bUpgrade linux-image-ibm-6.8Upgrade linux-image-5.15.0-1109-azureUpgrade linux-image-5.15.0-1100-awsUpgrade linux-image-ibm-classicUpgrade linux-image-nvidia-tegra-5.15Upgrade linux-image-5.15.0-1099-realtimeUpgrade linux-image-nvidia-tegra-rt-5.15Upgrade linux-image-raspi-realtimeUpgrade linux-image-ibmUpgrade linux-image-genericUpgrade linux-image-gcp-lts-22.04Upgrade linux-image-aws-64k-5.15Upgrade linux-image-5.15.0-1100-gcpUpgrade linux-image-realtime-hwe-22.04Upgrade linux-image-oracle-64k-6.8Upgrade linux-image-5.15.0-1052-nvidia-tegra-rtUpgrade linux-image-5.15.0-1097-raspiUpgrade linux-image-5.15.0-170-fipsUpgrade linux-image-generic-64k-6.8Upgrade linux-image-nvidia-lowlatency-6.8Upgrade linux-image-nvidiaUpgrade linux-image-raspi-nolpaeUpgrade linux-image-6.8.0-1050-raspiUpgrade linux-image-lowlatencyUpgrade linux-image-azure-lts-24.04Upgrade linux-image-virtualUpgrade linux-image-5.15.0-1064-xilinx-zynqmpUpgrade linux-image-oracle-64k-lts-24.04Upgrade linux-image-nvidia-tegraUpgrade linux-image-6.8.0-106-genericUpgrade linux-image-5.15.0-1100-gcp-fipsUpgrade linux-image-5.15.0-1100-aws-64kUpgrade linux-image-gke-5.15Upgrade linux-image-gcpUpgrade linux-image-azure-fips-6.8Upgrade linux-image-gcp-fipsUpgrade linux-image-gcp-64k-lts-24.04Upgrade linux-image-6.8.0-1050-awsUpgrade linux-image-6.8.0-1047-oracle-64kUpgrade linux-image-5.15.0-170-generic-64kUpgrade linux-image-oem-22.04cUpgrade linux-image-nvidia-tegra-igx-rt-5.15Upgrade linux-image-nvidia-tegra-igx-5.15Upgrade linux-image-nvidia-64k-hwe-22.04Upgrade linux-image-lowlatency-hwe-22.04Upgrade linux-image-lowlatency-64kUpgrade linux-image-5.15.0-170-genericUpgrade linux-image-fipsUpgrade linux-image-generic-64k-hwe-20.04Upgrade linux-image-generic-64kUpgrade linux-image-fips-6.8Upgrade linux-image-6.8.0-1049-nvidia-lowlatencyUpgrade linux-image-gkeopUpgrade linux-image-5.15.0-1095-intel-iotgUpgrade linux-image-oracle-lts-24.04Upgrade linux-image-oem-22.04aUpgrade linux-image-5.15.0-1095-nvidiaUpgrade linux-image-6.8.0-1048-gkeUpgrade linux-image-aws-lts-22.04Upgrade linux-image-generic-lpaeUpgrade linux-image-aws-6.8Upgrade linux-image-nvidia-lowlatency-64kUpgrade linux-image-azure-lts-22.04Upgrade linux-image-oem-22.04bUpgrade linux-image-5.15.0-1094-ibmUpgrade linux-image-6.8.0-1051-azureUpgrade linux-image-ibm-lts-24.04Upgrade linux-image-oracle-64kUpgrade linux-image-intelUpgrade linux-image-oem-20.04dUpgrade linux-image-xilinxUpgrade linux-image-5.15.0-1092-intel-iot-realtimeUpgrade linux-image-raspi-realtime-6.8Upgrade linux-image-6.8.0-1048-gke-64kUpgrade linux-image-xilinx-zynqmpUpgrade linux-image-gcp-fips-5.15Upgrade linux-image-5.15.0-1041-nvidia-tegra-igxUpgrade linux-image-virtual-6.8Upgrade linux-image-nvidia-6.8Upgrade linux-image-gkeop-5.15Upgrade linux-image-5.15.0-1097-oracleUpgrade linux-image-gcp-64kUpgrade linux-image-gke-64kUpgrade linux-image-raspi-6.8Upgrade linux-image-5.15.0-170-lowlatencyUpgrade linux-image-raspi-5.15Upgrade linux-image-kvmUpgrade linux-image-azure-cvmUpgrade linux-image-oracle-lts-22.04Upgrade linux-image-ibm-5.15Upgrade linux-image-gke-64k-6.8Upgrade linux-image-gcp-5.15Upgrade linux-image-6.8.0-1050-aws-64kUpgrade linux-image-5.15.0-1095-nvidia-lowlatencyUpgrade linux-image-azureUpgrade linux-image-azure-fips-5.15Upgrade linux-image-azure-5.15Upgrade linux-image-6.8.0-106-lowlatencyUpgrade linux-image-5.15.0-1052-nvidia-tegraUpgrade linux-image-raspiUpgrade linux-image-gcp-6.8Upgrade linux-image-nvidia-64kUpgrade linux-image-intel-iot-realtimeUpgrade linux-image-gcp-64k-6.8Upgrade linux-image-lowlatency-64k-hwe-22.04Upgrade linux-image-lowlatency-5.15Upgrade linux-image-aws-lts-24.04Upgrade linux-image-awsUpgrade linux-image-6.8.0-1052-azure-fipsUpgrade linux-image-6.8.0-1049-nvidia-64kUpgrade linux-image-realtimeUpgrade linux-image-nvidia-tegra-igxUpgrade linux-image-6.8.0-106-generic-64kUpgrade linux-image-5.15.0-1083-gkeopUpgrade linux-image-lowlatency-64k-6.8Upgrade linux-image-intel-iotgUpgrade linux-image-aws-64k-lts-24.04Upgrade linux-image-6.8.0-1052-gcp-fipsUpgrade linux-image-5.15.0-170-lowlatency-64kUpgrade linux-image-5.15.0-1109-azure-fipsUpgrade linux-image-6.8.0-106-lowlatency-64kUpgrade linux-image-aws-5.15Upgrade linux-image-6.8.0-1029-xilinxUpgrade linux-image-generic-lpae-5.15Upgrade linux-image-gke-6.8Upgrade linux-image-lowlatency-64k-hwe-20.04Upgrade linux-image-6.8.0-106-fipsUpgrade linux-image-5.15.0-1110-azureUpgrade linux-image-generic-hwe-22.04Upgrade linux-image-6.8.0-1049-nvidiaUpgrade linux-image-virtual-hwe-22.04Upgrade linux-image-virtual-hwe-20.04Upgrade linux-image-oracleUpgrade linux-image-oem-20.04cUpgrade linux-image-generic-64k-hwe-22.04Upgrade linux-image-6.8.0-1047-oracleUpgrade linux-image-xilinx-6.8Upgrade linux-image-virtual-5.15Upgrade linux-image-realtime-5.15Upgrade linux-image-nvidia-lowlatency-5.15Upgrade linux-image-oem-22.04dUpgrade linux-image-lowlatency-6.8Upgrade linux-image-lowlatency-64k-5.15Upgrade linux-image-generic-lpae-hwe-20.04Upgrade linux-image-generic-hwe-20.04Upgrade linux-image-azure-6.8Upgrade linux-image-6.8.0-1050-aws-fipsUpgrade linux-image-6.8.0-1052-gcpUpgrade linux-image-6.8.0-1049-nvidia-lowlatency-64kUpgrade linux-image-nvidia-hwe-22.04Upgrade linux-image-nvidia-5.15Upgrade linux-image-oracle-5.15Upgrade linux-image-gkeUpgrade linux-image-aws-fips-5.15Upgrade linux-image-realtime-6.8.1Upgrade linux-image-generic-5.15Upgrade linux-image-aws-fipsUpgrade linux-image-generic-64k-5.15Upgrade linux-image-gcp-lts-24.04Upgrade linux-image-aws-fips-6.8Upgrade linux-image-aws-64kUpgrade linux-image-6.8.0-2040-raspi-realtimeUpgrade linux-image-xilinx-zynqmp-5.15Upgrade linux-image-oracle-6.8Upgrade linux-image-oem-20.04Upgrade linux-image-nvidia-lowlatency-64k-6.8Upgrade linux-image-nvidia-lowlatency | Oct 30, 2025 | Oct 15, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | May 27, 2026 | Oct 15, 2025 |
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