Vulnerability in Linux

CVE-2026-68299

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (42.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-68299: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: -0.000

Affected products

  • Linux — versions 6.6.148, 7.2-rc5, 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc

References

Frequently asked questions

What is CVE-2026-68299?
CVE-2026-68299 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2026-08-10.
How severe is CVE-2026-68299?
High severity. CVSS v3 base score is 7.5 out of 10.