CVE-2023-52488

What it actually does

The flaw corrupts the regmap cache during multi-byte FIFO read/write operations on SC16IS7XX devices because regmap_raw_read() and regmap_raw_write() incorrectly assume register address incrementing, requiring manual cache disable as a workaround.

Why it matters to the business

Linux systems using the SC16IS7XX serial chip may encounter unreliable serial I/O or device misbehavior until kernels are updated, affecting embedded or industrial deployments with this hardware.

How an attack unfolds

An attacker with local access capable of triggering burst-mode FIFO operations on an affected SC16IS7XX device could induce regmap cache inconsistencies that lead to incorrect register handling or follow-on kernel issues.

How to fix it

Upgrade linux packages to fixed versions: Debian 12/13 to 6.1.8-1 or apply commit 4e37416e4ee1b1bc17364a68973e0c63be89e611 in stable kernels; rebuild and reboot with the corrected driver.

How to confirm the fix worked

Confirm kernel version matches or exceeds the listed fixed releases, verify FIFO access no longer requires manual cache disabling, and test serial burst transfers for correct operation.

Typical attack path

1. Identify systems exposing SC16IS7XX serial hardware
2. Trigger multi-byte FIFO access patterns via userspace or driver interaction
3. Observe or leverage resulting regmap cache corruption for further impact

How to detect it

Inspect kernel logs for sc16is7xx or regmap cache warnings during FIFO operations and correlate with device initialization events.

What your security team should do

• Prioritize kernel updates on systems with SC16IS7XX hardware
• Review serial device usage in embedded deployments for exposure
• Test patched kernels in staging before production rollout