After the Galaxy S24 series received the June 2024 security patch in some markets, it's the Galaxy S23 series' turn. As the name suggests, this update only improves security.
Both the June 2024 security patch for the Galaxy S24 series and Galaxy S23 series have arrived in the US. Among them, Galaxy S23, Galaxy S23+, and Galaxy S23 Ultra are being updated from a number of carriers, including T-Mobile and US Cellular. Other network-locked and non-locked products will also be available soon.
The baseband version of this update is S91xUSQS3CXE3. Due to improved security only, known bugs in One UI 6.1 for the Galaxy S23 series – such as rapid battery drain – are not fixed after you upgrade.
The June 2023 update patches 59 security vulnerabilities discovered on Samsung phones and tablets.
You can try downloading this update to your Galaxy S23, Galaxy S23+ or Galaxy S23 Ultra by navigating to the Settings app → Software Update → Download and install.