CVE-2024-36942

What it actually does

Memory leak in error path of Qualcomm Bluetooth (qca) firmware parsing in Linux kernel; firmware buffer not freed when post-commit sanity checks fail during controller download.

Why it matters to the business

Gradual memory exhaustion on systems with affected Bluetooth hardware can degrade performance or cause crashes in long-running servers, embedded devices, or Android kernels; low immediate urgency as not in KEV and no confirmed in-the-wild exploitation.

How an attack unfolds

An attacker supplies or triggers malformed firmware data that passes initial parsing but fails later sanity checks, repeatedly invoking the buggy error path to leak memory until the system is exhausted; threat actor references to Android kernel RCE remain unlinked to this specific leak.

How to fix it

Upgrade linux package on Debian 12 to 6.1.94-1 and on Debian 13 to 6.8.11-1; rebuild or backport the firmware buffer free on error path if custom kernels are required.

How to confirm the fix worked

Confirm kernel version matches or exceeds the listed fixed packages; exercise firmware load error paths in test environments and monitor for absence of leaks via kmemleak or slabinfo.

Typical attack path

1. Identify system using vulnerable qca Bluetooth driver
2. Cause repeated firmware load attempts that hit the sanity-check failure path
3. Accumulate unreleased buffers until memory pressure leads to denial of service

How to detect it

Review kernel logs for qca firmware load failures or sanity-check errors; use memory accounting tools to spot unexpected buffer growth tied to Bluetooth initialization.

What your security team should do

• Apply the listed Debian kernel updates on all affected hosts within standard patch windows
• Audit Bluetooth-enabled systems for qca hardware and prioritize servers or devices with long uptime
• Enable kernel memory debugging tools in staging environments to validate the fix