CVE-2026-43041 net: qrtr: replace qrtr_tx_flow radix_tree with xarray to fix memory leak
A memory leak in the Linux kernel's QRTR network subsystem can lead to resource exhaustion and denial of service.
- 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-2026-43041?
CVE-2026-43041 is a medium-severity denial of service vulnerability in Linux kernel, published on 1 May 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: qrtr: replace qrtr_tx_flow radix_tree with xarray to fix memory leak
__radix_tree_create() allocates and links intermediate nodes into the tree one by one. If a subsequent allocation fails, the already-linked nodes remain in the tree with no corresponding leaf entry. These orphaned internal nodes are never reclaimed because radix_tree_for_each_slot() only visits slots containing leaf values.
The radix_tree API is deprecated in favor of xarray. As suggested by Matthew Wilcox, migrate qrtr_tx_flow from radix_tree to xarray instead of fixing the radix_tree itself [1]. xarray properly handles cleanup of internal nodes — xa_destroy() frees all internal xarray nodes when the qrtr_node is released, preventing the leak.
[1] https://lore.kernel.org/all/[email protected]/T/
Weakness: CWE-401
Which versions are affected by CVE-2026-43041?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43041?
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-2026-43041 being exploited?
There is no known exploitation of CVE-2026-43041 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43041, DEBIAN-CVE-2026-43041, GHSA-vpmp-q24v-v7p4, ROOT-OS-DEBIAN-11-CVE-2026-43041, ROOT-OS-UBUNTU-2204-CVE-2026-43041, ROOT-OS-UBUNTU-2404-CVE-2026-43041 and 1 more.