CVE-2026-46214: vsock/virtio: fix accept queue count leak on transport mismatch

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-28 · updated 2026-10-15

Description

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix accept queue count leak on transport mismatch virtio_transport_recv_listen() calls sk_acceptq_added() before vsock_assign_transport(). If vsock_assign_transport() fails or selects a different transport, the error path returns without calling sk_acceptq_removed(), permanently incrementing sk_ack_backlog. After approximately backlog+1 such failures, sk_acceptq_is_full() returns true, causing the listener to reject all new connections. Fix by moving sk_acceptq_added() to after the transport validation, matching the pattern used by vmci_transport and hyperv_transport.

Affected products

Linux kernel: from 5.5 before 5.10.258; from 5.11 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.140; from 6.7 before 6.12.90; from 6.13 before 6.18.32 — fixed in 5.10.258, 5.15.209, 6.1.175, 6.12.90, 6.18.32, 6.6.140

How to fix

Upgrade to a fixed version: Linux kernel 5.10.258, 5.15.209, 6.1.175, 6.12.90. Check the vendor advisory for mitigations.

References

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