CVE-2024-53203

What it actually does

User-controlled command via debugfs allows con_index of zero to trigger array underflow when accessing ucsi->connector[con_index-1] in ucsi_ccg_sync_control, resulting in out-of-bounds memory read/write.

Why it matters to the business

Kernel memory corruption can cause system crashes, privilege escalation, or arbitrary code execution on affected Linux systems, increasing risk of downtime and data compromise especially where debugfs is accessible.

How an attack unfolds

An attacker with access to the debugfs interface supplies a crafted command that sets con_index to zero; the kernel then performs an underflow access into the connector array, enabling memory corruption that can be leveraged for further exploitation.

How to fix it

Update to a kernel containing the fix for CVE-2024-53203; disable or restrict debugfs access where possible until patched.

How to confirm the fix worked

Confirm kernel version includes the upstream commit resolving the array underflow; test debugfs command paths with con_index zero to verify no crash or corruption occurs.

Typical attack path

1. Obtain local access or debugfs privileges on a vulnerable kernel
2. Write crafted value to the ucsi_ccg debugfs control file
3. Trigger ucsi_ccg_sync_control with con_index of zero
4. Exploit resulting underflow for memory corruption or code execution

How to detect it

Review kernel logs for oops or warnings mentioning ucsi_ccg_sync_control or array underflow; inspect debugfs usage in audit logs for unusual command writes.

• ucsi_ccg_sync_control
• connector[con_index-1]
• debugfs.*ucsi

What your security team should do

• Apply the fixed kernel version immediately on all affected systems
• Restrict debugfs exposure to privileged users only
• Monitor for kernel oops or crashes related to ucsi_ccg
• Audit systems for unnecessary debugfs mounts