CVE-2026-74285 net: Stop leased rxq before uninstalling its memory provider
A race condition in Linux kernel network queue teardown allows DMA to stale addresses, potentially causing memory corruption or crashes.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74285?
CVE-2026-74285 is a high-severity vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net: Stop leased rxq before uninstalling its memory provider
netif_rxq_cleanup_unlease() tears down the memory provider that was installed on a physical RX queue through a netkit queue lease. It currently revokes the provider's DMA mappings before stopping the physical queue:
__netif_mp_uninstall_rxq(virt_rxq, p); /* DMA unmap */ __netif_mp_close_rxq(phys_rxq->dev, rxq_idx, p); /* queue stop */
This inverts the ordering used by the regular teardown paths (normal device unregister and the io_uring zcrx close path), which stop the queue before revoking the provider's mappings.
With the physical queue still live, its NAPI can keep consuming net_iov entries from the page_pool alloc cache after the __netif_mp_uninstall_rxq() has already cleared their dma_addr, opening a window for the device to DMA to a stale or zero address.
Fix it by swapping the two calls so the queue is stopped (and its NAPI quiesced) before the provider is uninstalled. No functional regression was observed across repeated runs of the nk_qlease.py HW selftest, which exercises the lease teardown path; this was tested against fbnic QEMU emulation.
Which versions are affected by CVE-2026-74285?
How do I fix CVE-2026-74285?
Apply the vendor's patch.
Is CVE-2026-74285 being exploited?
There is no known exploitation of CVE-2026-74285 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-74285, GHSA-v8cx-r8w6-r2xr, UBUNTU-CVE-2026-74285.