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From casual reading over the years, I've frequently encountered statements to the effect that hidden networks (i.e. wireless networks that does not broadcast its SSID) are unsafe, and that you should configure the wireless router with WPA2-PSK.

That implies that a hidden network and WPA2-PSK are mutually exclusive.
Or, put another way, that implies that a hidden network with X security is less secure than a non-hidden network with that same X security.
But my router seems to allow the capability to configure both independently, as in this screenshot:
enter image description here

Question:
Is a hidden network with "X" security less secure than a non-hidden network with that same "X" security (whether it is WPA2-PSK, or what have you)?
If yes, why?
That implies that hiding a network somehow "undoes" some aspect of the security provided by WPA2-PSK, etc. -- can someone please explain if this is so, and why?

StoneThrow
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3 Answers3

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A hidden network is generally regarded as being less secure for the client.

A client seeking to join a non-hidden network is able to passively listen for the access-point to broadcast it's identity. A client seeking to join a hidden network must itself broadcast "hello network ssid"

A rogue access-point overhearing these client broadcasts can pretend that it is the requested access-point. If the client accepts a connection to an unencrypted network as allowable (thankfully rare these days) then the rogue access-point has MiTM'ed the client.

user1725198
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No, they're not "less secure" – but they're also not more secure than normal networks, either. It would be unsafe to rely on hidden SSID as your primary security mechanism instead of WPA2.

(For example, a hidden network that uses legacy WEP can be discovered and cracked as easily as a non-hidden one, therefore it would be unsafe to use "but it's hidden" as an excuse to delay upgrading WEP networks to WPA2.)

Hidden networks handle WPA and WPA2 the same way as normal networks; the only difference is that instead of the access point revealing its name, client devices actively probe for it (and thus reveal its name wherever you go anyway), but otherwise the handshake proceeds as usual.

Hidden SSID is more appropriately used for point-to-point links where the client devices are statically configured for a specific network and having it show up in everyone's network list would only be unnecessary clutter (e.g. in a city there might be 10-20 Wi-Fi-based PtP links running above your head).

grawity
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Even if your network router is broadcasting the SSID, there are access point poising where a bad actor could just copy the exact name of a publicly broadcasted access point, and you as the client just happen to connect to it and start typing in a password. In a large populated area, if many people are trying to access that AP, that password can be intercepted pretty quickly. And now someone has access to a private network.

Ada
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