CVE-2017-10978

What it actually does

Read/write overflow in the make_secret() function allows an unauthenticated remote attacker to corrupt memory and trigger a denial of service.

Why it matters to the business

Disruption of RADIUS-based authentication services can cause widespread network access outages for users and devices until the server is restarted or patched.

How an attack unfolds

An attacker sends a specially crafted packet or configuration input that reaches the vulnerable make_secret() code path, causing memory corruption that crashes the FreeRADIUS process.

How to fix it

Upgrade FreeRADIUS 2.x to 2.2.10 or later and 3.x to 3.0.15 or later; the GIT repository is fixed by commit d253cf86d79b024ff68378e146775aa6975b887a. Restart services after upgrade and validate configurations.

How to confirm the fix worked

Confirm running version is at or above the fixed releases, review changelog for the referenced commit, and perform functional authentication tests under load to ensure stability.

Typical attack path

1. Identify exposed FreeRADIUS servers listening on UDP ports 1812/1813
2. Craft and transmit a malicious RADIUS request or shared-secret derivation input
3. Trigger the overflow inside make_secret() resulting in process crash
4. Repeat to maintain denial of service

How to detect it

Correlate RADIUS server process crashes with incoming request logs; look for repeated authentication failures or malformed packets immediately preceding restarts in system and application logs.

What your security team should do

• Immediately upgrade all instances to the fixed versions listed
• Restrict network exposure of RADIUS ports to only trusted clients
• Monitor process health and implement automated restarts with alerting
• Review downstream dependent packages for the same vulnerable code