168
votes
Accepted
Buying a "Used" Router
Short answer: do a factory reset, update the firmware, and you are good to go.
The risk is very low, bordering zero. The previous owner may have installed a custom firmware or changed its ...
- 52.8k
139
votes
If I delete my router's history can my ISP still provide it to my parents?
If I delete my router's history, is it still visible and can my ISP still provide it to my parents? Or is it deleted from existence?
Your ISP's record of your network usage isn't in any way affected ...
- 975
126
votes
Accepted
Did I just get DNS Hijacked?
Yes, your router's primary DNS entry was pointed to a rogue DNS server to make devices in your network resolve apple.com and other domains to phishing sites instead. The router possibly got ...
- 44.5k
102
votes
Accepted
Is removing the Ethernet cable from the router (when I'm not using it) a good security measure?
If there is not an internet connection to your device then a hacker is not going to be able to communicate with that device. (Edit: As some have pointed out...this is assuming an attacker is ...
- 1,748
84
votes
Do multiple routers increase security?
It may look good on paper, but it's a terrible idea.
You assume that the only way to get in your PC is from the first hop, the router closer to you, and that to hack one device, the previous one ...
- 52.8k
73
votes
Accepted
Somebody hacked my router and changed my wifi SSID
There are two different passwords that access different functions. If an attacker has the admin password, then he / she can change the SSID, WiFi password, and any other settings on the WiFi router.
...
- 2,042
68
votes
Accepted
Can someone without the WiFi login and no physical access to a router still access it with the admin login?
This may be possible using cross-site request forgery. In this attack, the attacker triggers a request to your router, for example by including an image on his site:
<img src="http://192.168.1.1/...
- 29.1k
56
votes
Accepted
Safe to download router firmware over unencrypted HTTP?
Sure - it could be a signed image. If the router has a built-in public key, and the image was signed by the corresponding private key, it would be perfectly safe.
Unless someone had got the private ...
- 27.3k
46
votes
Is it dangerous to use default router admin passwords if only trusted users are allowed on the network?
As you correctly noticed CSRF attacks are a possibility. Prevention of CSRF attacks is possible with a CSRF token, but this is nothing you can do as the user of the router. So if you are a router ...
- 196k
45
votes
Accepted
Is it dangerous to use default router admin passwords if only trusted users are allowed on the network?
Is it dangerous to use default router admin passwords if only trusted users are allowed on the network?
Yes, it's dangerous. Here are a few more "technical" ways to do it (other than saying ...
- 22.6k
43
votes
Accepted
Is it safe to buy a router if its serial number and other details are exposed on the web?
Yes this is safe.
Default password and PIN are irrelevant if you change them (or replace the firmware.)
Serial number is irrelevant anyway.
Part number is irrelevant anyway.
Which leaves the MAC ...
- 546
38
votes
If I delete my router's history can my ISP still provide it to my parents?
Routers usually do not store history and ISPs, while they may record such things on internal logs, do not give them out to anyone without a court order. You do not need to worry about your parents ...
- 66.3k
38
votes
What can be intercepted more easily, WiFi or Ethernet on a fully compromised router?
The medium doesn't matter. To the router's operating system, IP packets are IP packets are IP packets.
- 15.2k
35
votes
What are the security implications if someone got my home WiFi network password?
Giving the WiFi password away effectively gives full access to the local network. From there the guest might access the other computers inside the same network unless they have an additional ...
- 196k
32
votes
Accepted
Router being infected by malware
You don't need government grade malware to do this and such attacks have actually been carried out for years. Typical SOHO routers are often vulnerable to CSRF and similar attacks and this can be used ...
- 196k
32
votes
Is removing the Ethernet cable from the router (when I'm not using it) a good security measure?
This would reduce your risk by minimizing the time the attack surface is vulnerable to attack so yes technically it is a helpful security control. It falls into the category of Layer 1 access control ...
- 14.2k
31
votes
Is it something to worry about when my browser warns me that my connection to 192.168.1.1 (router admin page) is not secure?
No public Certificate Authority (CA) will issue a certificate for any IP address. Certificates are issued on domain names, and a basic DV certificates (like the ones that Let's Encrypt hands out) ...
- 5,990
29
votes
How to verify if router firmware is legitimate
There is no generic way to check if a downloaded firmware is the original one. A vendor might provide tools for this or not. But a properly designed update process would already include that the ...
- 196k
28
votes
Accepted
How to force clients to connect to WiFi automatically?
You can't simply Force a client, but to trick him!
As long as the device's WiFi is running, it keeps sending probe requests, searching for your previous connected networks. Using some software like ...
- 2,495
25
votes
What are the security implications if someone got my home WiFi network password?
Although it is not one of the things you listed in your question, he can engage in illegal activity over the internet which, when investigated by the authorities will render your IP as the source. ...
24
votes
Buying a "Used" Router
The main risk is that the firmware has been replaced by a malicious version, which could make it possible to intercept all the traffic on your network. Passwords, injecting malware, redirecting you to ...
- 127k
23
votes
Is it dangerous to use default router admin passwords if only trusted users are allowed on the network?
Yes, routers have been compromised by malware executing inside the network, testing a list of default passwords. The malware enters the network through an infected phishing attachment, or a browser ...
- 34.1k
23
votes
Safe to download router firmware over unencrypted HTTP?
It is probably safe.
But downloading over https should be preferred if possible.
Without https:
If there is a flaw in the signature mechanism, it can be exploited (example: https://github.com/...
- 2,095
21
votes
Is it dangerous to use default router admin passwords if only trusted users are allowed on the network?
I find it extraordinary that this question was asked, and I am not even a security professional. It is a bit like asking "Is it OK to leave the bank vault unlocked if only trusted cashiers are ...
- 227
21
votes
Did I just get DNS Hijacked?
It's obvious that someone changed DNS entries inside your router, probably using default credentials. You should go with factory reset, update your firmware, change default credentials and disable ...
- 10.1k
21
votes
Can someone without the WiFi login and no physical access to a router still access it with the admin login?
Almost all routers are configured by default to only expose the administration interface to the "LAN" side and not to the internet. Some routers have the option to enable or disable this, so it would ...
- 29.1k
19
votes
Dual Router Configuration
there are 7 layers in the OSI reference Model. a Network Firewall can protect you against attacks upto Layer 4. there are still 3 more layers out there that are unprotected. so, no matter what you do ...
- 2,347
18
votes
Buying a "Used" Router
By far, your main risk in buying an "open box" router is that the router has some subtle damage that the manufacturer didn't detect but that will ultimately reduce the lifespan of the device. That's ...
- 1,121
16
votes
Accepted
Can I protect my router from a Mirai Worm and how do I know if I'm vulnerable?
Like your quote says; change the password. It would be much harder to fix if Mirai used 'actual' vulnerabilities (software bugs i.e. memory corruption). Then you'd have to hope there's an update ...
- 4,803
15
votes
Is removing the Ethernet cable from the router (when I'm not using it) a good security measure?
Given how many attacks are aimed at routers, the number of security flaws / backdoors in consumer grade routers, and the fact your router is an always-on gateway to the big bad internet, I'd say ...
- 367
Only top scored, non community-wiki answers of a minimum length are eligible