CVE-2026-63970

Sažetak

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: bind uarg before filling zerocopy skb virtio_transport_send_pkt_info() allocates or reuses the zerocopy uarg before entering the send loop, but virtio_transport_alloc_skb() still fills the skb before it inherits that uarg. When fixed-buffer vectored zerocopy hits MAX_SKB_FRAGS, io_sg_from_iter() may partially attach managed frags and return -EMSGSIZE. The rollback path call kfree_skb() to free an skb that carries SKBFL_MANAGED_FRAG_REFS but no uarg, so skb_release_data() falls through to ordinary frag unref. Pass the uarg into virtio_transport_alloc_skb() and bind it immediately before virtio_transport_fill_skb(). This keeps control or no-payload skbs untouched while ensuring success and rollback share one lifetime rule.

Reference

CVSS

Base:	7.8
Impact:	5.9
Exploitability:	1.8

Pristup

Vektor	Složenost	Autentikacija
LOCAL	LOW	LOW

Impact

Povjerljivost	Cjelovitost	Dostupnost
HIGH	HIGH	HIGH

CVSS vektor

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

Zadnje važnije ažuriranje

20-07-2026 - 15:16

Objavljeno

19-07-2026 - 16:17