CVE-2026-72017 net: macb: drop in-flight Tx SKBs on close
A memory leak in the Linux kernel MACB network driver can lead to resource exhaustion and denial of service when network interfaces are closed.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72017?
CVE-2026-72017 is a memory corruption vulnerability in Linux, published on 15 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:
net: macb: drop in-flight Tx SKBs on close
The MACB driver has since forever leaked the outgoing SKBs that have not yet been marked as completed. They live in queue->tx_skb which gets freed without remorse nor checking.
macb_free_consistent() gets called in a few codepaths, but only close will trigger the added expressions. In macb_open() and macb_alloc_consistent() failure cases, queues' tx_skb just got allocated and are empty.
Which versions are affected by CVE-2026-72017?
How do I fix CVE-2026-72017?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-72017 being exploited?
There is no known exploitation of CVE-2026-72017 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72017, DEBIAN-CVE-2026-72017, GHSA-v3cw-v56w-xqgw, UBUNTU-CVE-2026-72017.