CVE-2026-74459 can: etas_es58x: es58x_read_bulk_callback(): fix RX buffer leak on URB resubmit failure
A memory leak in the Linux kernel CAN driver allows attackers to cause denial of service by triggering URB resubmit failures.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74459?
CVE-2026-74459 is a denial of service 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:
can: etas_es58x: es58x_read_bulk_callback(): fix RX buffer leak on URB resubmit failure
es58x_read_bulk_callback() resubmits the RX URB after processing a received packet. If the resubmit succeeds, the URB remains anchored and will be handled by the normal RX path or by teardown.
However, if usb_submit_urb() fails, the callback unanchors the URB and then returns directly. This skips the existing free_urb path, so the coherent transfer buffer allocated with usb_alloc_coherent() is not released.
Reuse the existing free_urb path after a resubmit failure so that the RX coherent buffer is freed before leaving the callback.
Which versions are affected by CVE-2026-74459?
How do I fix CVE-2026-74459?
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-2026-74459 being exploited?
There is no known exploitation of CVE-2026-74459 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74459, DEBIAN-CVE-2026-74459, GHSA-5m9p-vm8m-7vmc, UBUNTU-CVE-2026-74459.