CVE-2024-27068

What it actually does

A memory leak occurs in the Mediatek LVTS thermal driver when devm_krealloc() fails to reallocate the efuse buffer, leaving the original allocation unfreed in the error path.

Why it matters to the business

Affected Linux systems on Mediatek platforms risk gradual kernel memory exhaustion during repeated driver error conditions, potentially causing performance degradation or requiring reboots in long-running embedded or server environments.

How an attack unfolds

An attacker with local access or the ability to induce hardware/driver probe failures could repeatedly trigger the error path in lvts_thermal to leak memory until system resources are depleted, though the low EPSS and lack of KEV listing indicate this is not a practical remote attack vector.

How to fix it

Update the Linux kernel to include commit 2db869da91afd48e5b9ec76814709be49662b07d which adds the missing free of efuse on devm_krealloc failure.

How to confirm the fix worked

Confirm the fix is present by inspecting the lvts_thermal.c source for the added kfree on error or by running a patched kernel version containing 2db869da91afd48e5b9ec76814709be49662b07d.

Typical attack path

1. Gain local access or induce repeated probe failures on Mediatek hardware
2. Trigger devm_krealloc failure conditions in the LVTS driver
3. Accumulate unfreed efuse allocations to exhaust kernel memory

How to detect it

Search kernel logs for LVTS driver probe or initialization failures combined with steadily increasing slab or kmalloc memory usage on Mediatek platforms; no public exploitation artifacts are known.

What your security team should do

• Prioritize kernel updates containing commit 2db869da91afd48e5b9ec76814709be49662b07d on all Mediatek-based systems
• Review systems for any custom thermal driver modifications that may reintroduce similar leaks
• Monitor kernel memory usage trends on affected hardware as a defense-in-depth measure