CVE-2026-45994: Linux Kernel

High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: ibmasm: fix OOB reads in command_file_write due to missing size checks The command_file_write() handler allocates a kernel buffer of exactly count bytes and copies user data into it, but does not validate the buffer against the dot command protocol before passing it to get_dot_command_size() and get_dot_command_timeout(). Since both the allocation size (count) and the header fields (command_size, data_size) are independently user-controlled, an attacker can cause get_dot_command_size() to return a value exceeding the allocation, triggering OOB reads in get_dot_command_timeout() and an out-of-bounds memcpy_toio() that leaks kernel heap memory to the service processor. Fix with two guards: reject writes smaller than sizeof(struct dot_command_header) before allocation, then after copying user data reject commands where the buffer is smaller than the total size declared by the header (sizeof(header) + command_size + data_size). This ensures all subsequent header and payload field accesses stay within the buffer.

Affected products

• Linux Linux Kernel: from 2.6.12.1, before 5.10.258 (fixed in 5.10.258); from 5.11, before 5.15.209 (fixed in 5.15.209); from 5.16, before 6.1.175 (fixed in 6.1.175); from 6.2, before 6.6.140 (fixed in 6.6.140); from 6.7, before 6.12.86 (fixed in 6.12.86); from 6.13, before 6.18.27 (fixed in 6.18.27); …

Published 2026-05-27. Last modified 2026-06-17.