CVE-2024-42258

What it actually does

Incorrect preprocessor condition (CONFIG_X86_32 instead of !CONFIG_64BIT) fails to relax huge page alignment on all 32-bit architectures such as x86_32, leaving a latent memory management flaw in huge_memory handling.

Why it matters to the business

Potential crashes or degraded stability on any remaining 32-bit Linux systems running vulnerable kernels, increasing operational risk until patched; low urgency given age and limited 32-bit deployments.

How an attack unfolds

A local attacker with low privileges triggers huge page allocation paths on an affected 32-bit system; the faulty alignment logic causes the kernel to mishandle memory, resulting in denial of service.

How to fix it

Upgrade Linux kernel to 6.1.105 or later, or apply commit 89f2914dd4b47d2fad3deef0d700f9526d98d11f; rebuild and reboot all affected 32-bit systems.

How to confirm the fix worked

Verify running kernel version is at or above the fixed release; confirm CONFIG_64BIT is absent and huge page alignment logic uses !CONFIG_64BIT; test huge page allocation workloads for stability.

Typical attack path

1. Obtain local shell on target 32-bit Linux system
2. Trigger memory operations that request huge pages
3. Kernel applies incorrect alignment check due to config macro mismatch
4. System encounters alignment failure leading to crash or hang

How to detect it

Review kernel logs for huge page alignment warnings or oops on 32-bit systems; no post-exploitation artifacts are known.

What your security team should do

• Prioritize patching any remaining 32-bit Linux systems within maintenance windows
• Audit inventory for 32-bit kernel usage and schedule decommissioning where feasible
• Monitor vendor advisories for backports to older LTS branches