CVE-2025-21831 PCI: Avoid putting some root ports into D3 on TUXEDO Sirius Gen1
A kernel bug causes system hangs during suspend on specific TUXEDO hardware, requiring a patch to prevent root ports from entering D3 state.
- 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-2025-21831?
CVE-2025-21831 is a medium-severity denial of service vulnerability in Linux kernel, published on 6 Mar 2025. 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:
PCI: Avoid putting some root ports into D3 on TUXEDO Sirius Gen1
commit 9d26d3a8f1b0 ("PCI: Put PCIe ports into D3 during suspend") sets the policy that all PCIe ports are allowed to use D3. When the system is suspended if the port is not power manageable by the platform and won't be used for wakeup via a PME this sets up the policy for these ports to go into D3hot.
This policy generally makes sense from an OSPM perspective but it leads to problems with wakeup from suspend on the TUXEDO Sirius 16 Gen 1 with a specific old BIOS. This manifests as a system hang.
On the affected Device + BIOS combination, add a quirk for the root port of the problematic controller to ensure that these root ports are not put into D3hot at suspend.
This patch is based on
https://lore.kernel.org/linux-pci/[email protected]
but with the added condition both in the documentation and in the code to apply only to the TUXEDO Sirius 16 Gen 1 with a specific old BIOS and only the affected root ports.
Which versions are affected by CVE-2025-21831?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-21831?
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-2025-21831 being exploited?
There is no known exploitation of CVE-2025-21831 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-69009, BELL-CVE-2025-21831, DEBIAN-CVE-2025-21831, GHSA-m4j5-fq6h-r8gv, ROOT-OS-DEBIAN-11-CVE-2025-21831, ROOT-OS-DEBIAN-12-CVE-2025-21831 and 2 more.