CVE-2023-52524

What it actually does

Missing lock around NFC LLCP device list modifications creates a race condition that can corrupt kernel list structures.

Why it matters to the business

Systems using Linux NFC LLCP may experience kernel instability or crashes, increasing downtime risk on affected servers and devices; the issue has been present for years with no known active exploitation campaigns.

How an attack unfolds

An attacker with local access triggers concurrent NFC device list operations that race without the required lock, allowing list corruption; no named threat actors or public exploits are associated with this flaw.

How to fix it

Update the Linux kernel to a fixed version such as 5.4.258 or apply commit 191d87a19cf1005ecf41e1ae08d74e17379e8391 from the stable repository; rebuild and reboot with the patched kernel.

How to confirm the fix worked

Confirm the running kernel version is at or above a listed fixed release and verify the presence of the locking calls around device list modifications in the llcp source.

Typical attack path

1. Obtain local access to a system running an affected Linux kernel with NFC LLCP enabled
2. Trigger multiple concurrent operations that modify the NFC device list
3. Exploit the missing lock to corrupt internal kernel list structures
4. Cause denial of service via kernel panic or memory corruption

How to detect it

Search kernel logs and crash dumps for NFC LLCP list corruption symptoms or concurrent modification warnings; no public indicators of active exploitation exist.

What your security team should do

• Prioritize kernel updates on all systems exposing NFC LLCP functionality
• Review and restrict local user access where NFC is not required
• Monitor vendor advisories for additional stable backports