CVE-2026-74626 NTB: ntb_netdev: Preserve RX queue depth on allocation failure
Attackers can cause network reception stalls in the Linux kernel NTB driver by triggering memory allocation failures that deplete the RX queue.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74626?
CVE-2026-74626 is a high-severity denial of service vulnerability in Linux, published on 22 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
NTB: ntb_netdev: Preserve RX queue depth on allocation failure
ntb_netdev_rx_handler() hands the received skb to the network stack before allocating its replacement. If the allocation fails, nothing is reposted. Every failure therefore takes one buffer out of the RX queue while the interface remains up, and enough failures eventually stall reception.
A retry path could refill the queue later, but ntb_netdev has none. Allocate the replacement first instead. If that fails, drop the packet and repost the same skb. This keeps the queue full and lets packet delivery resume as soon as memory is available again.
Which versions are affected by CVE-2026-74626?
How do I fix CVE-2026-74626?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-74626 being exploited?
There is no known exploitation of CVE-2026-74626 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74626, DEBIAN-CVE-2026-74626, GHSA-2vc2-fj43-9qhc, UBUNTU-CVE-2026-74626.