CVE-2026-31412
What it is
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_mass_storage: Fix potential integer overflow in check_command_size_in_blocks() The `check_command_size_in_blocks()` function calculates the data size in bytes by left shifting `common->data_size_from_cmnd` by the block size (`common->curlun->blkbits`). However, it does not validate whether this shift operation will cause an integer overflow. Initially, the block size is set up in `fsg_lun_open()` , and the `common->data_size_from_cmnd` is set up in `do_scsi_command()`. During initialization, there is no integer overflow check for the interaction between two variables. So if a malicious USB host sends a SCSI READ or WRITE command requesting a large amount of data (`common->data_size_from_cmnd`), the left shift operation can wrap around. This results in a truncated data size, which can bypass boundary checks and potentially lead to memory corruption or out-of-bounds accesses. Fix this by using the check_shl_overflow() macro to safely perform the shift and catch any overflows.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-190 · Integer overflow
- Record status
- Analyzed
Affected
- Linux Kernel < 6.1.167
- Linux Kernel < 6.6.130
- Linux Kernel < 6.12.78
- Linux Kernel < 6.18.19
- Linux Kernel < 6.19.9
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-31412.md and follow it. Check whether this project is affected by CVE-2026-31412. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/228b37936376143f4b60cc6828663f6eaceb81b5
- https://git.kernel.org/stable/c/3428dc5520c811e66622b2f5fa43341bf9a1f8b3
- https://git.kernel.org/stable/c/387ebb0453b99d71491419a5dc4ab4bee0cacbac
- https://git.kernel.org/stable/c/8479891d1f04a8ce55366fe4ca361ccdb96f02e1
- https://git.kernel.org/stable/c/91817ad5452defe69bc7bc0e355f0ed5d01125cc
- https://git.kernel.org/stable/c/ce0caaed5940162780c5c223b8ae54968a5f059b
References
- https://git.kernel.org/stable/c/228b37936376143f4b60cc6828663f6eaceb81b5
- https://git.kernel.org/stable/c/3428dc5520c811e66622b2f5fa43341bf9a1f8b3
- https://git.kernel.org/stable/c/387ebb0453b99d71491419a5dc4ab4bee0cacbac
- https://git.kernel.org/stable/c/8479891d1f04a8ce55366fe4ca361ccdb96f02e1
- https://git.kernel.org/stable/c/91817ad5452defe69bc7bc0e355f0ed5d01125cc
- https://git.kernel.org/stable/c/ce0caaed5940162780c5c223b8ae54968a5f059b