CVE-2026-80978

Last refreshed2026-10-17

Status: UPDATED | Advisory ID: CVE-2026-80978

Key Details

CVE	CVE-2026-80978
CVSS Score / Version	7.8 (High) / CVSS v3.1
Updated	2026-10-16
CVSS Vector	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
CVSS Prose	attack vector is local; attack complexity is low; privileges required is low; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is high; availability impact is high.
Affected products	Linux Kernel

Vendor	Product	Affected Versions	Patch Status
Linux	Linux Kernel

Vendor

Product

Affected Versions

Patch Status

Linux

Linux Kernel

Subsystems	OT Supporting Infrastructure
Sectors	All Sectors

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

net: cap advertised IP tunnel headroom

IP tunnel devices derive their advertised needed_headroom from lower

output devices. A stack of user-created devices can make the derived

value larger than the 16-bit skb header offsets can represent. Once IP

output reserves it, skb head expansion can wrap those offsets.

The runtime transmit path already caps a growing needed_headroom at 512.

Apply the same cap when tunnel configuration publishes needed_headroom

derived from a lower output device.

Capping the advertised value is safe: IP tunnel transmit still expands

the skb when a packet needs more headroom. A nonsensical stacked

configuration can therefore incur an extra reallocation, but it cannot

publish an unbounded reservation to upper layers. (NVD)

Monitor Linux's web page for any future patch releases.

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-80978
CVE	https://www.cve.org/CVERecord?id=CVE-2026-80978

Source

Reference

NVD

CVE