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Decrypt Cisco Secret 44/22/2021
All these password locations represent good access locations for passwords, but if you have only one password on only one access location, you should at least have an enable password.This password gives you security on your router, because Privileged EXEC mode is where all the dangerous commands are located, including access to Global Configuration mode.To view this password, show the running configuration using the following command.
The password is stored in plain text in your configuration file, thus anyone who has access to your configuration file can easily read the password. When you configure both an enable and a secret password, the secret password is the password that will be used to switch from User Exec mode to Priv Exec mode. You may also see a 0, which identifies it as an unencrypted password. He holds the Cisco CCNA and numerous other certifications, and has provided system and LAN support to both large and small organizations. Ed is coauthor of CompTIA A Certification All-in-One For Dummies. Bottom line: Either one of these is WAY more secure then type 5s and almost infinity more secure then the horrible broken type 4s. Tip: If the failing expression is known to be legally refer to something thats sometimes null or missing, either specify a default value like myOptionalVarmyDefault, or use when-present when-missing. These only cover the last step of the expression; to cover the whole expression, use parenthesis: (myOptionalVar.foo)myDefault, (myOptionalVar.foo). For me this is new, is there a documentation which describes the function of these two options 8 and 9 Why is the option 4 no longer availalbe, is there any security concerns Should be AES-256 as as far as I know, this option is really secure. For example, when you create your enable password, it is encrypted. The second part is the device encrypting the password in the config so they cant be reversed and recovered. This was even obvious from the configuration - identical passwords lead to identical encoded hash strings. It still took months and some external researchers to notify Cisco that something is wrong, and it ended with a PSIRT advisory roughly a year ago. And then, for the following several months, latest IOS versions still bugged you to use secret 4 even when you insisted on old-but-at-least-salted MD5 secrets. Decrypt Cisco Secret 4 Generator To AvoidIve even used an external generator to avoid this pitfall until fixed implementations finally made it to customers (which is what happened over the last weeks). Now secret 5 is again the default (when you just enter enable secret bla, it will generate an MD5 hash again) and the new solutions are pushed a lot less aggressively than was the disaster of secret 4. Give them a year for some external cryptologists to seriously probe them before ever touching them. BTW, secret 4 had to go as it was unfixable - they could have implemented the method correctly, but it would have invalidated all the hashes existing in configurations out there. Its still getting an interesting transition period now, away again from busted secret 4. Sorry for the rant, but this has been a pet peeve of mine, I had to discuss this with a lot of customers over the last 9 months or so. HTH, Andre. While good, this is still vulnerable to brute-forcing since SHA-256 is easy to implement VERY fast in ASICS or graphics cards. That is not to say its easy, and in fact if you choose good passwords it is close to impossible, but it is doable Type 9: Type 9 passwords use the scrypt algorithm from the crypto-currency guys. Its whole goal is to ensure that it is expensive to run the algorithm. It does this first by being hard to run in parallel and by requiring a tradeoff: Either use lots of memory and be fast or a little memory and be slow. The trick there is that ASICS and graphics cards dont have enough memory (memory BW) to run fast so in practice it is VERY SLOW to run this algorithm. The other interesting thing is that inside the algorithm is.Lots of PBKDF2 so in Scrypt you combine the best of both.
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