The iptables tag has no wiki summary.
4
votes
2answers
70 views
Executing arbitrary commands through iptables-restore input
During a pentest I found a way to add arbitrary iptables firewall rules to a server. These rules get applied by way of the iptables-restore command, and I've been wondering whether there is any way to ...
0
votes
1answer
75 views
Securing my firewall (both dedicated and iptables-based) [closed]
I have an ASA-5510, but I also intend to maintain strict IP tables on my server (Ubuntu 12.04.2), so that there are two layers of "protection".
My iptables look like this:
*filter
# Allows all ...
0
votes
3answers
115 views
How can i reject connection from LAN and WAN to some ports?
Scanning with nmap, I discovered that there are 3 open ports on my server. I want to deny any access to these ports from any machine, regardless of whether it is on the same LAN or via WAN. How do I ...
1
vote
2answers
269 views
Test firewall rules (Linux)
I have a question about how to test the firewall rules. To be more specific, for academic purpose I have to set up a machine which will accept all kind of packets o a specific interface.
I added an ...
1
vote
2answers
167 views
How to configure iptables for must open ports?
On my machine there are web services which can be accessed from any PC connected to the same network segment (WiFi for example). I want to use IPtables on the machine to prevent any web services from ...
0
votes
1answer
195 views
icmp packets not able to reach the firewall despite of adding a specific rule, why?
I am using iptables to allow the icmp traffic in/out of my host. Please find below are the entries from my firewall (linux based):-
[root@localhost ~]# iptables -L
Chain INPUT (policy DROP)
target ...
0
votes
3answers
268 views
Some issues with iptables and nmap
When I scan my pc with nmap I see only one open port. I didn't define any rule in iptables so if I'm not mistaken, all connections should be denied by default.
However I can use HTTP or SSH, so that ...
2
votes
1answer
115 views
Consequences of using -s and -d arguments in iptables
We are studying iptables for a Computer Systems Security course. We are confused as to what happens when the -s and -d arguments are both used in the same rule, such as:
iptables -A OUTPUT -s ...
1
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2answers
355 views
How is iptables useful to prevent attacks against a LAN?
I need some advice securing a LAN using iptables.
I've found lots of examples on how to secure single host with iptables, including scanning ports, attacking using ICMP-flood and TCP-flood. These ...
1
vote
1answer
164 views
IPtables - Accept Arbitrary Packets
I've achieved a lot on blocking attacks on GameServers but I'm stuck on something. I've blocked major requests of game-server which it aceepts in the form "\xff\xff\xff\xff" which can be followed by ...
1
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3answers
1k views
Ignoring broadcasts to 10.0.0.255 using iptables
I'm trying to drop logging packets that are destined for 10.0.0.255 by using the following rules:
$IPTABLES -A OUTPUT -d 10.0.0.255 -j DROP
$IPTABLES -A FORWARD -d 10.0.0.255 -j DROP
It ...
3
votes
2answers
231 views
Can ipopts be used to circumvent a pf or iptables firewall source IP based blocking?
Can one use ipopts, and in particular IP source routing, to circumvent source-based blocking in pf or iptables?
For example, with OpenBSD's pf:
block in all # default deny
block out all
pass in on ...
4
votes
4answers
9k views
Tips for a secure iptables config to defend from attacks. (client side!)
Own examples:
###############
# KERNEL PARAMETER CONFIGURATION
# PREVENT YOU SYSTEM FROM ANSWERING ICMP ECHO REQUESTS
echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all
# DROP ICMP ECHO-REQUEST ...
0
votes
2answers
2k views
IPTables default security rules for a gateway/router?
On a router such as dd-wrt or tomato, what would be some default iptables rules?
I am asking for rules on a router/gateway - For example; blocking SYN flood attacks, or XMAS attacks. The basic ...
4
votes
4answers
924 views
what is a good public available iptables script for ddos mitigation?
what is a good public available iptables script for ddos mitigation?
4
votes
4answers
666 views
Firewall demo - iptables
I have to make a demonstration about firewalls in my class as a student(university).
It should be implemented using iptables on Linux. I am reading all the theories around them but I can't figure out ...
10
votes
2answers
1k views
Reject IP packets with an ICMP error, or just drop them?
Consider an internet-facing host (the outer firewall). What should be done with undesired traffic: just drop it, or send back an ICMP error such as port unreachable? (In Linux terms: iptables -P DROP ...
