CVE-2024-28956

What it actually does

The flaw exposes sensitive information stored in shared microarchitectural structures of affected Intel processors during transient execution, allowing an authenticated local user to disclose data via local access.

Why it matters to the business

Potential leakage of sensitive information on systems using vulnerable Intel processors could result in data exposure or privacy incidents; low and stable EPSS with no KEV listing indicates limited active exploitation risk, though older Ubuntu webkitgtk deployments remain exposed until updated.

How an attack unfolds

An authenticated local attacker runs code that triggers transient execution paths on the CPU, observes side effects in shared microarchitectural buffers, and reconstructs sensitive data without requiring elevated privileges beyond local access.

How to fix it

Upgrade webkitgtk on Ubuntu 14.04 LTS to version 2.4.8-1ubuntu1~ubuntu14.04.1 and on Ubuntu 16.04 LTS to 2.4.9-2ubuntu2; apply any vendor microcode or firmware updates for affected Intel processors and verify the updates are active.

How to confirm the fix worked

Confirm installed webkitgtk package versions match or exceed the listed fixed releases and check processor microcode revision against vendor guidance for transient-execution mitigations.

Typical attack path

1. Obtain authenticated local access to the target system
2. Execute unprivileged code that induces speculative transient execution
3. Measure microarchitectural state changes to infer and exfiltrate sensitive information

How to detect it

Examine system logs for unusual local process activity involving speculative execution or cache timing measurements; correlate with any unexpected data access patterns on affected hardware.

What your security team should do

• Prioritize patching affected Ubuntu systems with the specified webkitgtk fixed versions
• Review local access controls and limit unnecessary authenticated accounts on systems with Intel processors
• Monitor EPSS trend and threat actor activity for any increase in exploitation attempts