Method and apparatus for protecting a web server against vandals attacks without restricting legitimate access
View Patent ↗An intrusion detection security system (IDSS) guards a server against vandals' attacks such as denial of service, distributed denial of service, and common gateway interface attacks. An incoming source address is compared with the contents of a database of privileged addresses. If the incoming address is present in the database, the IDSS instructs protective equipment such as a firewall or router to allow the incoming message to pass to the web server despite any ongoing attack, thus allowing messages from customers or suppliers, for example, through. Otherwise, the IDSS checks a database of blocked addresses. When the incoming address is absent, the IDSS writes the address to the database of blocked addresses and instructs the protective equipment to block subsequent messages from the incoming address.
1. A method for improving the operation of equipment used to protect a web server against attack, comprising the acts of:
reading a source address of a message received during an attack;
checking a database of privileged source addresses; and
instructing protective equipment for a web server to pass the received message to the web server, regardless of an ongoing attack, when the source address of the received message matches an address contained in the database of privileged source addresses;
when the source address of the received message does not appear in the database of privileged source addresses, checking a database of blocked source addresses; and
when the source address of the received message does not appear in the database of blocked source addresses, adding the source address of the received message to the database of blocked source addresses.
2. The method of claim 1 , wherein the database of privileged source addresses includes a source address of a customer known to the web server.
3. The method of claim 1 , wherein the database of privileged source addresses includes a source address of a user known to the web server.
4. A method for improving the operation of equipment used to protect a web server against attack by a vandal, comprising the acts of:
reading a source address of a message received during an attack;
checking a database of privileged source addresses for appearance of the source address of the received message;
when the source address of the received message appears in the database of privileged source addresses, instructing protective equipment to pass the received message to a web server;
when the source address of the received message does not appear in the database of privileged source addresses, checking a database of blocked source addresses for appearance of the source address of the received message; and
when the source address of the received message does not appear in the database of blocked source addresses, adding the source address of the received message to the database of blocked source addresses and instructing the protective equipment to block the received message and to block subsequent messages that bear the source address of the received message.
5. Protective equipment for guarding a web server against attack, comprising:
an address decoder for reading a source address of a message received during an attack;
a database of privileged source addresses;
a database of blocked source addresses; and
logic for instructing protective equipment for a web server to pass the message received during the attack to the web server when the source address of the message received during the attack matches a privileged source address contained in the database of privileged source addresses, regardless of an ongoing attack;
when the source address of the received message does not appear in the database of privileged source addresses, checking the database of blocked source addresses; and
when the source address of the received message does not appear in the database of blocked source addresses, adding the source address of the received message to the database of blocked source addresses.
6. The protective equipment as set forth in claim 5 , wherein the database of privileged source addresses includes a source address of a customer known to access the web server.
7. The protective equipment as set forth in claim 5 , wherein the database of privileged source addresses includes a source address of a known user of the web server.
8. Protective equipment for guarding a web server against attack, comprising:
an address decoder for reading a source address of a message received during an attack;
a database of privileged source addresses, which passes a packet containing a privileged source address to the web server regardless of an ongoing attack;
a database of blocked source addresses; and
logic for checking the database of privileged source addresses and the database of blocked source addresses for appearance of the source address of the message received during the attack and, responsive to the appearance, instructing protective equipment to block incoming messages that bear the source address of the message received during the attack;
when the source address of the received message does not appear in the database of privileged source addresses, checking the database of blocked source addresses; and
when the source address of the received message does not appear in the database of blocked source addresses, adding the source address of the received message to the database of blocked source addresses.
9. Protective equipment for guarding a web server against attack, comprising:
an address decoder for reading a source address of a message received during an attack;
a database of privileged source addresses;
a database of blocked source addresses; and
logic for:
checking the database of privileged source addresses for appearance of the source address of the received message;
when the source address of the received message appears in the database of privileged source addresses, instructing protective equipment to pass the received message to a web server, regardless of an ongoing attack;
when the source address of the received message does not appear in the database of privileged source addresses, checking the database of blocked source addresses for appearance of the source address of the received message; and
when the source address of the received message does not appear in the database of blocked source addresses, adding the source address of the received message to the database of blocked source addresses and instructing the protective equipment to block the received message and to block subsequent messages that bear the source address of the received message.
10. A method for improving the operation of equipment used to protect a web server against attack, comprising the acts of:
reading a source address of a message received during an attack;
checking a database of privileged source addresses;
instructing protective equipment for a web server to pass the received message to the web server, regardless of an ongoing attack, when the source address of the received message matches an address contained in the database of privileged source addresses;
detecting cessation of the attack;
removing one or more source addresses used by an attacker from a database of blocked source addresses; and
unblocking the one or more source addresses just removed.