CVE-2026-63970 (GCVE-0-2026-63970)

Vulnerability from cvelistv5 – Published: 2026-07-19 14:55 – Updated: 2026-08-05 12:37
VLAI
Title
vsock/virtio: bind uarg before filling zerocopy skb
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 54/100 over 6618 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 72194f65050958e4c8e069adb6c5d89ef81ca197 (git)
Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < b62e2b2b4a50953ca952f3cd3f77dd62dc50fd5d (git)
Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 5d317573f1d48e76cce5fb6250452b6e4102e0fb (git)
Affected: 581512a6dc939ef122e49336626ae159f3b8a345 , < 1e584c304cfb94a759417130b1fc6d30b30c4cce (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.7
Unaffected: 0 , < 6.7 (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.35 , ≤ 6.18.* (semver)
Unaffected: 7.0.12 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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}



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