CVE Catalog

CVE-2026-80932

HighCVSS 8.4
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel, virtio_vsock_remove() stops the virtqueues and flushes each work item before freeing the enclosing virtio_vsock, but the order does not account for dependencies: tx_work may queue send_pkt_work, and send_pkt_work may queue rx_work. In particular, send_pkt_work can set restart_rx and release tx_lock, and the remove path can flush rx_work before send_pkt_work queues it, leading to a use-after-free race with kfree(vsock).

Risk Assessment

The use-after-free race in the vsock/virtio module can lead to kernel memory corruption and system crash (KASAN reported slab-use-after-free). It can be triggered by vsock socket operations during device removal.

Recommendation

Update the Linux kernel to a version with the fix that flushes works in producer-to-consumer order (tx_work, send_pkt_work, rx_work).

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: flush works in dependency order virtio_vsock_remove() stops the virtqueues and then flushes each work item before freeing the enclosing virtio_vsock. The current order does not account for dependencies between those items: tx_work may queue send_pkt_work, and send_pkt_work may queue rx_work. In particular, send_pkt_work can set restart_rx and release tx_lock. The remove path can then stop the queues and flush rx_work before send_pkt_work queues it. Although the later send_pkt_work flush waits for that producer to finish, nothing waits for the newly queued rx_work, so kfree(vsock) can race with it. KASAN reported: BUG: KASAN: slab-use-after-free in virtio_transport_rx_work+0x487/0x4b0 Read of size 8 at addr ffff888114c2b008 by task kworker/1:1/47 Workqueue: virtio_vsock virtio_transport_rx_work Call Trace: virtio_transport_rx_work+0x487/0x4b0 process_one_work+0x688/0x1120 worker_thread+0x45b/0xd10 Allocated by task 1: virtio_vsock_probe+0xef/0x6b0 Freed by task 84: kfree+0x131/0x3c0 virtio_vsock_remove+0xd1/0x100 Flush the works in producer-to-consumer order. virtio_vsock_vqs_del() has already disabled the queue callbacks and cleared the run flags, so after tx_work and send_pkt_work are drained, no source remains that can queue rx_work after its flush.

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