Echo: linux: security update to 6.1.158-1

high Tenable Cloud Security Plugin ID 463654

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

- 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.
(CVE-2025-39985)

Solution

Update the linux library and its related packages to version 6.1.158-1 or later.

Plugin Details

Severity: High

ID: 463654

Version: Revision 1.1

Type: Local

Family: Echo Local Security Checks

Published: 10/2/2026

Updated: 10/2/2026

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.12

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2025-39985

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 10/16/2025

Vulnerability Publication Date: 10/10/2025

Reference Information

CVE: CVE-2025-39985

Detections

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