CVE-2026-90063

medium

Description

In the Linux kernel, the following vulnerability has been resolved: virtio-net: Ensure that TCP packets don't overflow gso_segs The user can specify any gso_size in a packet crafted with an AF_PACKET PACKET_VNET_HDR socket, even smaller than TCP_MIN_GSO_SIZE = 8. At the same time, GSO_MAX_SIZE = 8 * GSO_MAX_SEGS = 8 * 65535. When the user crafts a packet with gso_size < 8, there is a risk for partial GSO to overflow the 16-bit gso_segs field when dividing the SKB length by gso_size. Adjust gso_size of TCP packets to be at least TCP_MIN_GSO_SIZE = 8. Keep gso_size of UDP GSO packets, as gso_size=1 is valid and explicitly tested at tools/testing/selftests/net/tun.c:649.

References

https://git.kernel.org/stable/c/d3d111fe809773edbb4ae121e36253b7d683509a

https://git.kernel.org/stable/c/c27c449d455aafd9018a3cbab150f1c42c87923f

https://git.kernel.org/stable/c/8f6667a081887c2b59c6f3dd86c1789ada563762

https://git.kernel.org/stable/c/75c271c48f483af678e514734e10b2452410e08c

https://git.kernel.org/stable/c/339f47ae04dcc6b5a730dd6bc70dddc8937c3260

https://git.kernel.org/stable/c/29bd12c7c5f9d6cf855b87bace18f71e9607f9e8

https://git.kernel.org/stable/c/0e5ed3b98d1d8d251acfdccfeaa607453ad12954

Details

Source: Mitre, NVD

Published: 2026-09-17

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 7.2

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

Severity: High

CVSS v3

Base Score: 5.5

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

EPSS

EPSS: 0.00206