CVE-2026-68299

HIGH
7.5CVSS v3
CVSS v2
0.50% EPSS (exploit probability)
CWE

Description

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

vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets

vmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the
outer header, but for a Geneve-encapsulated packet the device can set
them based on the inner header instead, signalled by the
VMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the
function never skips the outer encapsulation, this mismatch triggers:

- BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer
protocol is UDP (Geneve), not TCP.
- BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner
IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa).

Check VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the
function cannot locate the inner header it would need to parse. Also
convert the remaining BUG_ON()s in this function to return 0
defensively.

CVSS v3 vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected routers (0)

No routers currently mapped to this CVE in our database.

External references