CVE-2024-50290

What it actually does

Failed SNR register reads in the cx24116 driver return negative values, causing an integer underflow during subsequent SNR calculus operations and potential memory corruption.

Why it matters to the business

Systems using affected Linux kernel media drivers may experience crashes or instability when handling DVB devices, increasing operational risk and requiring urgent patching on high-prevalence kernel deployments.

How an attack unfolds

An attacker triggers repeated failed SNR register reads in the cx24116 driver to induce underflow conditions that corrupt memory structures, potentially leading to denial of service or escalation when combined with other kernel primitives.

How to fix it

Upgrade affected packages to the fixed versions: flashplugin-nonfree (Ubuntu:14.04:LTS) to 11.2.202.554ubuntu0.14.04.1. Apply kernel updates containing the cx24116 SNR fix and verify with package managers.

How to confirm the fix worked

Confirm the driver no longer returns negative SNR values on register failure by inspecting source or running targeted media device tests post-upgrade.

Typical attack path

1. Obtain local or remote access to trigger media device SNR queries
2. Force failed register reads in cx24116 driver
3. Induce underflow in SNR calculation
4. Leverage resulting memory corruption for further exploitation

How to detect it

Review kernel logs for cx24116 SNR register read failures or underflow warnings; inspect media subsystem crash dumps and dmesg output for negative value propagation artifacts.

What your security team should do

• Prioritize kernel and media driver updates within 30 days given publication age
• Audit systems for cx24116 usage and apply fixed flashplugin-nonfree package where present
• Monitor EPSS and threat actor reports for any increase in exploitation attempts