PSA: Manually update your Synology NAS right now

Synology NAS owners should take the network storage devices offline and manually update them as soon as possible, especially for older units.
Synology DS420+
The discovery of vulnerabilities in PHP led to large sections of the Internet updating servers to patch the software flaws. This doesn't just affect commercial webservers, as it is also a problem for home NAS units, including those with services that are accessible over the Internet.The PHP fiasco should've been a warning for everyone to st