Out-of-bounds read in Linux kernel - CVE-2026-23375

Detailed vulnerability description

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper access control in the file_thp_enabled() function when handling files on anonymous inodes via processing memory operations. A local user can trigger memory operations such as MADV_COLLAPSE or rely on khugepaged activity to cause a kernel crash or trigger erroneous memory failure reports.

Exploitation does not require elevated privileges but requires the ability to create or access files on anonymous inodes such as guest_memfd or secretmem. The impact includes system crash or spurious memory failure warnings in the kernel log.

How to mitigate CVE-2026-23375

Sources

• https://git.kernel.org/stable/c/0524ee56af2c9bfbad152a810f1ca95de8ca00d7
• https://git.kernel.org/stable/c/08de46a75f91a6661bc1ce0a93614f4bc313c581
• https://git.kernel.org/stable/c/dd085fe9a8ebfc5d10314c60452db38d2b75e609
• https://git.kernel.org/stable/c/f6fa05f0dddd387417d0c28281ddb951582514d6