CVE Catalog

CVE-2026-63970

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

6th percentile - higher than 6% of all known CVEs

Summary

Vulnerability in the Linux kernel in the vsock/virtio driver related to incorrect uarg binding before filling zerocopy skb. Can lead to improper memory management and potential data leak.

Risk Assessment

May lead to system crashes or incorrect zerocopy behavior, affecting system performance and stability.

Recommendation

Apply the Linux kernel patch that moves uarg binding before skb filling. Update the kernel to a version containing the fix.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS