Linux Kernel virtio driver Vulnerability Rated 7.1 CVSS

Status: UPDATED  |  Advisory ID: CVE-2026-74684

Key Details

Affected Products, Subsystems & Sectors

What to Know

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

net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()

The commit 4f61f133f354 ("net: tap: NULL pointer derefence in

dev_parse_header_protocol when skb->dev is null") fixed a crash in

tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().

This is required because virtio_net_hdr_to_skb() may invoke

dev_parse_header_protocol(), which dereferences skb->dev. Without the

assignment, a NULL pointer dereference can occur.

However, tap_get_user_xdp() still parses the virtio-net header before

assigning skb->dev. When the vhost TX path passes an XDP buffer containing

a GSO virtio-net header but the protocol is set to zero on purpose,

tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev

is still NULL, resulting in a crash.

Fix this by looking up the tap device and assigning skb->dev before calling

tun_vnet_hdr_to_skb(), matching the ordering already used in

tap_get_user(). Preserve the existing RCU read-side critical section across

dev_queue_xmit(). (NVD)

What to Do

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

References