CVE-2023-54295 mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type
A shift-out-of-bounds error in the Linux kernel's SPI NOR flash driver can cause a denial of service when masking erase types.
- 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-2023-54295?
CVE-2023-54295 is a vulnerability in Linux, published on 30 Dec 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:
mtd: spi-nor: Fix shift-out-of-bounds in spi_nor_set_erase_type
spi_nor_set_erase_type() was used either to set or to mask out an erase type. When we used it to mask out an erase type a shift-out-of-bounds was hit: UBSAN: shift-out-of-bounds in drivers/mtd/spi-nor/core.c:2237:24 shift exponent 4294967295 is too large for 32-bit type 'int'
The setting of the size_{shift, mask} and of the opcode are unnecessary when the erase size is zero, as throughout the code just the erase size is considered to determine whether an erase type is supported or not. Setting the opcode to 0xFF was wrong too as nobody guarantees that 0xFF is an unused opcode. Thus when masking out an erase type, just set the erase size to zero. This will fix the shift-out-of-bounds.
[ta: refine changes, new commit message, fix compilation error]
Which versions are affected by CVE-2023-54295?
How do I fix CVE-2023-54295?
Apply the vendor's patch.
Is CVE-2023-54295 being exploited?
There is no known exploitation of CVE-2023-54295 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54295, DEBIAN-CVE-2023-54295, GHSA-3x4v-mgvj-ccrv, UBUNTU-CVE-2023-54295.