Executive brief
The silabser.sys driver for Silicon Labs CP210x USB-to-serial devices contains a vulnerability that allows a local user with physical access to connect a specially crafted malicious device. By sending malformed packets, an attacker can read up to 145 bytes of sensitive uninitialized kernel memory, potentially exposing data from other processes. This affects Windows systems with CP210x driver v11.5.0 and earlier.
Technical details
The vulnerability is an information disclosure (kernel pool memory leak) in the silabser.sys driver that handles CP210x USB serial device communication. A local attacker with physical access can create a malicious CP210x device that transmits malformed packets to trigger the leak. The attack requires no elevated privileges and no network access, only the ability to connect a rogue USB device to the target system. The flaw leaks up to 145 bytes of uninitialized kernel pool memory per exploit instance. Patches are available from Silicon Labs in driver versions after 11.5.0.
Affected products
- Silicon Labs CP210x silabser.sys driver v11.5.0 and earlier
Timeline
- 2026-09-10: disclosed