CVE-2025-40157 EDAC/i10nm: Skip DIMM enumeration on a disabled memory controller
A local attacker can cause a kernel crash on Intel Granite Rapids servers by triggering a shift-out-of-bounds error in the EDAC driver during initialization.
- 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-2025-40157?
CVE-2025-40157 is a denial of service vulnerability in Linux, published on 12 Nov 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:
EDAC/i10nm: Skip DIMM enumeration on a disabled memory controller
When loading the i10nm_edac driver on some Intel Granite Rapids servers, a call trace may appear as follows:
UBSAN: shift-out-of-bounds in drivers/edac/skx_common.c:453:16 shift exponent -66 is negative ... __ubsan_handle_shift_out_of_bounds+0x1e3/0x390 skx_get_dimm_info.cold+0x47/0xd40 [skx_edac_common] i10nm_get_dimm_config+0x23e/0x390 [i10nm_edac] skx_register_mci+0x159/0x220 [skx_edac_common] i10nm_init+0xcb0/0x1ff0 [i10nm_edac] ...
This occurs because some BIOS may disable a memory controller if there aren't any memory DIMMs populated on this memory controller. The DIMMMTR register of this disabled memory controller contains the invalid value ~0, resulting in the call trace above.
Fix this call trace by skipping DIMM enumeration on a disabled memory controller.
Which versions are affected by CVE-2025-40157?
How do I fix CVE-2025-40157?
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-2025-40157 being exploited?
There is no known exploitation of CVE-2025-40157 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40157, DEBIAN-CVE-2025-40157, GHSA-rr63-42vx-4m23, ROOT-OS-DEBIAN-13-CVE-2025-40157, ROOT-OS-UBUNTU-2404-CVE-2025-40157, UBUNTU-CVE-2025-40157.