CVE-2024-21820

What it actually does

Incorrect default permissions in Intel Xeon processor memory controller configurations with SGX allow a privileged local user to escalate privileges.

Why it matters to the business

Attackers who already have local privileged access could gain broader system control, increasing risk of data theft or service disruption; low EPSS and no KEV status indicate limited known exploitation but still requires prompt patching on affected systems.

How an attack unfolds

An attacker with local privileged access leverages the misconfigured SGX memory controller permissions to elevate their privileges further on the system.

How to fix it

Apply the listed fixed versions for affected packages such as giflib (Ubuntu:16.04:LTS) updated to 5.1.2-0.1; verify configuration of Intel SGX on Xeon processors and apply vendor microcode or firmware updates where applicable.

How to confirm the fix worked

Confirm package versions match fixed releases like giflib 5.1.2-0.1 and review system configurations for SGX memory controller permissions after updates.

Typical attack path

1. Gain local privileged access to the target system
2. Identify vulnerable Intel Xeon SGX memory controller configuration
3. Exploit incorrect default permissions to escalate privileges

How to detect it

Review authentication and privilege change logs for unexpected escalations on systems with SGX enabled; check package inventories for outdated giflib or Intel microcode versions.

What your security team should do

• Prioritize patching affected systems within standard change windows given stable low EPSS
• Audit local privileged access controls on systems using Intel SGX
• Monitor for any new exploit maturity signals or threat actor mentions