Tag: Security

  • Configure MD5 encrypted passwords for users on Cisco IOS

    The enhanced password security in Cisco IOS introduced in 12.0(18)S allows an admin to configure MD5 encryption for passwords. Prior to this feature the encryption level on Type 7 passwords used a week encryption and can be cracked easily and the clear text password (type 0) as anyone would know is completely insecure. Anyone who can gain access to the privilege mode can view/decrypt these passwords.

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  • Enable/Configure DHCP Snooping in Cisco Catalyst Switches (IOS)

    DHCP snooping is a DHCP security feature that provides security by filtering untrusted DHCP messages and by building and maintaining a DHCP snooping binding table. An untrusted DHCP message is a message that is received from outside the network or firewall causing denial of service attacks.

    The DHCP snooping binding table contains the MAC address, IP address, lease time, binding type, VLAN number, and interface information that corresponds to the local untrusted interfaces of a switch. An untrusted interface is an interface that is configured to receive messages from outside the network or firewall. A trusted interface is an interface that is configured to receive only messages from within the network.

    DHCP snooping can be enabled on the switch per vlan as it can intercept the DHCP messages at the layer2.

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  • VLAN Hopping – Layer 2 Security exploit bypass Layer 3 security

    VLAN Hopping is a Layer 2 security exploit by which a malicous user connected to a switchport on a Switch assigned to a VLAN can hop on and gain access to another VLAN which otherwise is not accessible. This security exploit allows the malicous hacker to bypass the IP Securities implemented at Layer 3.

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  • How to Add a Banner in Cisco IOS Routers and Switches

    Banners are one of the important things for any device that allows remote access either for administration or for user access. They serve their purpose of warning any unauthorised users and make them aware that the device or the server is protected and being monitored and also provide a quick snapshot of what the system is and what is it used for. For example, we use banners for security warning and the device details and the service/application related to it.

    Adding a Banner to Cisco Router or a Catalyst switch running Cisco IOS is all a matter of one simple command.

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  • Secure yourself from Phishing attacks with NetCraft Toolbar

    Phishers send well crafted emails as if coming from a valid source like your bank tricking you to enter your bank account or any portal (like eBay or Paypal) details including login and password or PIN numbers . Once, you enter the details, they are sent to remote servers. Now, that’s more than anything for the hackers to loot money out of your account.

    Taking security seriously, we will discuss the community aided Netcraft tool bar for Internet Explorer & Firefox. First of all, I have to applaud NetCraft toolbar as by far the best toolbar that you can get for free. When I tested a new eBay scam email URL, no other toolbar other than NetCraft can catch the Phishing URL.

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  • Secure Internet Explorer browsing with Haute Secure plugin

    Haute Secure is a free Internet Explorer plugin that secures you from loading bad content or malicious content or download and install malware onto your PC. When the Haute Secure add-on on your internet explorer comes across bad content it will block access to the website and prompt you for further option. It will also warn of malicious content try to load from known website. With Phishing scams, malicious malware spreading minute and the identity theft scams, it is important that we secure the browsers thereby no malicious content is downloaded onto the PC. Haute Secure supports only Internet Explorer at the moment but Firefox is expected to be onboard soon. There is also a Windows Vista 64 bit supported version available download. (more…)