I have a problem since two days. I am facing a DoS attack on one of my IP's with 20Mbit of UDP Packets.
These are the packets I receive:
Code:
16:19:26.949003 IP (tos 0x0, ttl 49, id 14236, offset 0, flags [DF], proto: UDP (17), length: 29) 222.90.73.53.33713 > foo.com.www: [udp sum ok] UDP, length 1
My provider says they can't do anything. The only thing they could do is shut down my IP. Which is not really helpful. I have no idea what to do or what else I could analyze.
It would be very interesting if the IP is being attacked or one of the sites I host.
I have already over 300GB traffic since yesterday because of this.
I'm sure that i have Trojans and Viruses on my Server but every time i contacted My Company they ask me to pay money and then they will check and scan my server
so is it any Free application which can scan and remove all bad files on my Server? i'm looking for free applications to scan the whole server
My server stop responding, I couldn't access via webmin or ssh, and DNS were not responding, so I have to ask for a reboot and now everything is fine.
Looking at the logs I found this:
Code: Jul 18 19:23:12 server sshd[18484]: Failed password for root from 61.145.196.117 port 56817 ssh2 Jul 18 19:23:12 server sshd[18485]: Failed password for root from 61.145.196.117 port 60227 ssh2 Jul 18 19:23:13 server sshd[18488]: Failed password for root from 61.145.196.117 port 38038 ssh2 Jul 18 19:23:15 server sshd[18493]: Failed password for root from 61.145.196.117 port 49884 ssh2 Jul 18 19:24:30 server sshd[18497]: Failed password for root from 61.145.196.117 port 37929 ssh2 Jul 18 19:25:06 server sshd[18521]: Did not receive identification string from 61.145.196.117 Jul 18 19:25:09 server sshd[18508]: Did not receive identification string from 61.145.196.117 Jul 18 19:25:14 server sshd[18505]: fatal: Timeout before authentication for UNKNOWN Jul 18 19:26:00 server sshd[18509]: Did not receive identification string from 61.145.196.117 And searching that IP on google I found it here: http://www.tcc.edu.tw/netbase/net/in...?fun=240&prd=3
And is flagged as a SSH Attack.
Any ideas why my server stopped working? and how to prevent it?
My site currently in prolong HTTP flood attack since 2 weeks ago. The attack was never stop and for this moment i could only mitigate the attack using my own firewall (hardware).
Since my ISP is not interested to help from upstream, even provide any mitigation services, i could only doing mitigation on my own source or using proxy services alternatively as well, but i've chose to tried on my own. I've tried once on one of well-known mitigation services out there but it seems not fully satisfied me since most of legitimate traffic is blocked from their source.
What i could do now is keep staying alive as well as will not going down on whatever situation becomes worst (but if the attack change to udp attack, i couldn't help myself coz there must be high incoming bandwidth into my network). My network is totaling 10MB last time but since this attack i've been forced to subscribe for 30MB in order to keep balance on the attack.
I've blocked all access except for my country and some other neighbours. If i change policy to allow all countries, the load of firewall will become max and after that hang will hang in less than a minute. I've done load balancing of 4 servers (8GB memory each one) and it seems the condition is getting under control with slight problem of server hang (memory shortage) and very limited keep alive connection.
Now what am i thinking is to buy a router objectively to null route incoming specific IP of countries so i can change my firewall policy to allow all connections as well as to help the firewall itself release its burden halting blocked IP that currently keep hitting itself that could might impact its performance.
Which brands of router is possible doing this thing?
Do you have some other suggestions instead of buying router?
i am just having one issue in one of my highly visited website hangibar.com, its being hosted in softlayer, we are facing synattack too much in this website.
the solution which microsoft given in their website related with tcp/ip registry entry but thing is same , some where and some connections become increases too much over tcp/ip. due to that reason website become very sticky and it stop functioning the execution of sql process, during this issue i have to restart the server to establish a fresh connection.
When i tried to view this http://gihkus.com/Lnx.txt it seems to be attack on my server. http://gihkus.com/Lnx.txt is not hosted by us. I have disabled perl support on all domains hosted on our server but still we are under attack. There is nothing special in /tmp.
Over the past day one of my servers has seen a huge rise in incomming traffic (from normal web requests to a constant 4Mbit/s, peaking upto 80Mbit/s). My outgoing traffic has remained at its normal profile, so I am pretty sure that these are not web requests, and it does not seem to be having an adverse effect on the server (the site still runs perfectly well and quick and load is still less than 1).
However, I am unsure as to how to identify what this traffic is? Are there any easy ways to tell on a FreeBSD server what the source and type of incomming traffic is? I have tried playing with netstat, but an not getting anything useful - I would like to see which ports are involved.
Am Really suffering here for ddos attack ( apache - pop3 ) every week my server under attack am using APF but now am really wanna get red from it am looking for a powerfull firewall I do not know if CSF Could stop this attack like limiting receiving SYN from an ip or any other policy another thing . i have get this rules from forums but am really weak at iptables rules so can any one help my if these rules useful or not . against Dos attack:
iptables -t nat -N syn-flood iptables -t nat -A syn-flood -m limit --limit 12/s --limit-burst 24 -j RETURN iptables -t nat -A syn-flood -j DROP iptables -t nat -A PREROUTING -i eth0 -d (dest ip) -p tcp --syn -j syn-flood
I have a windows server, and today it has a large inbound traffic, so I tried to disable all web service, and after that, the result of netstat -an shows no connection at all, but the server still has large inbound traffic,
i had installed anti ddos or firewall,but those are useless.His attacks are such great that The server and all the vps are down now. One told me that I should check the ips and receive ips. The attacker is so skillful .describe the best method to defeat him. Be sides the attacker use diffirenet ips in each attack,I block him by iptables but no use…. His attack occupy all the ram and I have to resetart the server… Now this time his attack lead to shutting all the vps down
My website is under ddos attack from some competitors. I don't know yet how big is the attack. The ips of the ddos attack come from all the world.
I have contacted a few hosting companies specialised in ddos proof hosting, unfortunatly the price is so expensive that i cannot afford it.
So i try to find another solution : my website is only aimed to the french people, so maybe is it possible to install a kind of firewall or proxy located before the server to block all the incoming IP adress not from france ? Do you know some websites who can do this and the price ?
I already try do deny the non-french ip in one htaccess file but the ddos attack saturate the server anyway.
We are currently experiencing an SYN Flood attack on our primary production server and are looking for some help in resolving the issue.
Running: Novell SUSE Linux Enterprise Server 10.2-64 SuperMicro X7DBR-E Intel Xeon QuadCore DualProc SATA [2Proc] Processor Intel Xeon-Clovertown 5320L-QuadCore [1.86GHz] 8GB Memory @ Softlayer DC in Texas.
Need help within the next hour or two. Please ask any necessary follow up questions and how you might go about resolving the issue (i.e. SYN Cookies, etc.)
It's literally thousands of those requests overloading apache. The server is fine, the load average is like .8. But none of the website are loading.
We're hosting with ThePlanet, and they're doing a great job at blocking a huge portion of the attack. But we're still getting hit pretty hard. I've got APF installed, and 3 or 4 anti-dos scripts.
Every once in a while a page will load for the websites, I think we've got just under 50 legit connections.
In addition, please send us any source files of the attack.
Please let us know if you have any questions or need further assistance. We appreciate your cooperation.
RSA Anti-Fraud Command Center RSA, The Security Division of EMC "
I look at subdomains...and I dont have any, I look at .htaccess nothing, look at 404 page, nothing..also look at template files and no any iframe or similar?
I would like to know what are the best ways in preventing a UDP D/DoS Attack. DDoS-Deflate and most programs like that are just for TCP connections, and most of the time only for port 80. What is the best option out there for protection (linux wise) for UDP attacks. I was using shorewall before but it did not do so well so I just switched now to CSF [url] with WebMin and seems to be working ok. Even though thoes are both firewalls, they seem to have some protection against UDP Attacks. Please note this is a server that just hosts some game servers, no webhosting. What would be my best option here?
I'm hosting my website on a shared hosting, and recently the ip 87.255.1.42 began sending DoS attacks to my website - there are constantly being sent queries to the starting page of my website, more than 400,000 queries/day.
It's not doing any significant damage but overloads the server every day, and I would like to know how to report this attack to any authority who can stop the attack.
I queried the RIPE database db.ripe.net/whois?form_type=simple
It seems that one domain at a cpanel server has been inyected with some iframe code... the problem seems to be that we can not find the iframe code anywhere in the public_html directory.
We already scanned the site public_html directory trying to find the js file or something that can launch the iframe but it seems to be impossible to find, also ran clamscanner in the fold without sucess.
I was thinking about some mod_security rule to block iframe js attacks, does anybody know about this?
This is a RHE 4 + cPanel server, This is the iframe code:
