CVE-2026-97947 x86/amd_node: Fix potential NULL pointer dereference
A local attacker can trigger a NULL pointer dereference in the Linux kernel's AMD node driver, causing a system crash.
- 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-2026-97947?
CVE-2026-97947 is a vulnerability in Linux, published on 25 Sep 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:
x86/amd_node: Fix potential NULL pointer dereference
amd_smn_read/write() are exported functions around __amd_smn_rw(), so they are always available even if amd_smn_init() fails. In that case, 'amd_roots' is NULL and __amd_smn_rw() will access uninitialized memory.
Then, commit:
83518453074d ("x86/amd_node: Add SMN offsets to exclusive region access")
added the 'smn_exclusive' flag, which indicated the calls to pci_request_config_region_exclusive() succeeded, to prevent concurrent userspace access.
Commit:
0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
re-ordered initialization so pci_request_config_region_exclusive() is called earlier and a failure exits amd_smn_init() before allocating 'amd_roots'. The setting of 'smn_exclusive' moved to the end of amd_smn_init(), after 'amd_roots' is allocated. It became redundant and can be removed.
Replace 'smn_exclusive' with directly checking 'amd_roots', to fix a potential NULL pointer dereference and to simplify the logic.
[ bp: Reorg commit message, touchup comment. ] [ mingo: Rebase & further touchups. ]
Which versions are affected by CVE-2026-97947?
How do I fix CVE-2026-97947?
Apply the vendor's patch.
Is CVE-2026-97947 being exploited?
There is no known exploitation of CVE-2026-97947 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-97947, DEBIAN-CVE-2026-97947, GHSA-xj5r-4m42-gc82, UBUNTU-CVE-2026-97947.