If you’re reading PCWorld, you probably know that it’s important to keep your PC updated so that security issues are patched. And you probably know the same is true for your phone, and even things like a PlayStation. But don’t forget that your network gear is also, basically, just a bunch of computers. And thank Asus for reminding us, as it patches DSL routers to close exploitable security flaws.
Specifically, Asus has issued a firmware update for three models of relatively old DSL routers with combination Wi-Fi functionality: the DSL-AC51, the DSL-N16, and the DSL-AC750. Released in 2015 and 2017, at least as far as I can tell from a quick search, these are fairly straightforward models without super advanced features even for the time. But if you happen to have one in your home, you want to patch that firmware post-haste. They’re susceptible to an authentication bypass vulnerability, as published on the multi-vendor record Common Vulnerabilities and Exposures (CVE) database and spotted by Bleeping Computer.
The direct Asus support pages for the DSL-AC51, the DSL-N16, and the DSL-AC750 are there, in the links that I just posted in that sentence. Firmware can be downloaded and applied via the web-based interface for most routers, if it hasn’t already done so automatically or manually applied by downloading the file and then uploading it in the GUI over the local network.
What if your router is susceptible to this particular vulnerability, but it’s out of service and not getting patched? Then Asus suggests that you disable basically all advanced functions, including remote WAN access, port forwarding, DNS, VPN server, DMZ, port triggering, and FTP. Which specific older, unsupported DSL routers does this apply to? Don’t ask me because Asus is not saying.
I don’t have DSL, but it occurred to me that I don’t know the brand and model of my cable modem or Wi-Fi router off the top of my head. I think I’ll dig into the rat’s nest behind my printer, just so I can write them down somewhere a little more accessible.