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-1
votes
1answer
17 views

Server Blocked by Provider Sending UDP Packages to certain IP - what does that mean?

My webserver got blocked by my provider recently for the reason that it was performing an attack to another server. The email contained the following log: 08:26:39.219940 68:05:ca:07:02:01 > ...
0
votes
0answers
16 views

Bad Referer AND DNS Cache Poisoning [duplicate]

I am annoyed by a lot of bad referer spammers I am seeing in apache's logs. 208.118.126.250 - - [12/May/2015:17:45:06 +0200] "GET /js/parsley.js HTTP/1.1" 200 91434 "http://voiceit.be/logins/login" ...
0
votes
0answers
9 views

Vultr modsec check (Spam Attempt) [duplicate]

i received vultr's warning spam email, that said: 1 attacks from x.x.x.x has been detected against malekal.com and when i contacted support, he told me use tcpdump (but i'm new here, i dont know ...
-3
votes
0answers
32 views

How to disable Symbolic link creation option to users in cPanel server? [closed]

In shared hosting server, one user is trying to upload 100s of symbolic link files and trying to access files out side. Mostly it is for malicious purpose. In this image, you can see 100s of symlink ...
0
votes
0answers
65 views

Apache access_log return 200 when file not exist

I found a thread Apache reports status 200 but file doesn't exist in the server My server is recently being attacked; I received many GET request to "/cgi-bin/" and a few other categories. Most ...
1
vote
1answer
48 views

Server attack but on Upload not Download

I am currently being attacked on one of my servers, but I am struggling to find out what could be causing it. I have had a few DDoS attacks before but this particular attack, which I'm not sure what ...
1
vote
0answers
108 views

How to block hping3 SYN ACK efficiently with iptables?

Actually I'm trying to execute a SYN TCP flood on my Debian web server with nginx and, by executing tcpdump "tcp[tcpflags] & (tcp-syn) != 0" while flooding, I see all packets coming. I already ...
-1
votes
1answer
33 views

web application audit task require my remote IP to be allowed on application network firewall [closed]

I want to audit a web application which is hosted on a web server sitting behind a cyberoam firewall. My task is to run a scan from my remote machine which has ISP MTNL broadband. My machine gets a ...
0
votes
1answer
69 views

Any way to block DNS response using BIND?

I am using BIND as my DNS-server. I have disabled recursive DNS-request. Now I am under some kind of attack. Is there any was to block this or do I have to let it go? My query log: client ...
0
votes
1answer
32 views

What is a typical request rate per hour in a distributed attack?

I am concerned that some static files hosted publicly in S3 can be the target of an attack that aims to hurt me financially (ramping up my AWS bills). I have set up a logging system, that runs every ...
0
votes
2answers
405 views

Email server attack from telnet

My mail server having a problem on blocking some attacker that trying to telnet to our mailserver. but i'm not able to block it, ip will keep changing even we block by ip. seems like he is trying to ...
-1
votes
2answers
146 views

How to null route a dns zone [closed]

I have a domain that was attacked and flooding the server apache system. The only way to detour the attack is to reroute the dns off the server. Is there a generic IP like "127.0.0.1" that I can use ...
-10
votes
3answers
1k views

make fail2ban use public blacklists [closed]

I've been searching high and low for a way to connect fail2ban with blocklist.de (or any other public blacklists, for that matter, as long as fail2ban can report to it). Pretty much every result that ...
1
vote
2answers
62 views

Can't block spammy IP

I'm being attacked by 37.59.4.76. It's sending me a great amount of data, which is destroying my dataplan. I've added the iptables Chain num pkts bytes target prot opt in out ...
0
votes
0answers
49 views

Server usage topped 100% and crashed - how to diagnose and prevent

I'm running a small webserver on Ubuntu 12.04. Last night, the server topped off at 100% cpu usage and crashed. This is unusual as I'm normally around 1-5%. I suspect a DDoS attack from someone ...
1
vote
1answer
83 views

Another domain points to my webserver

Somebody else has registered a name pointing to my webserver's IP address in .ma TLD. My domain foo.bar -> my ip address 1.2.3.4 Somebody defined: suspiciousdomain.ma -> my ip address 1.2.3.4 So ...
0
votes
2answers
215 views

How to block requests for virtual hosts that dont exist in apache [duplicate]

First up, check out this question: Why are external domains appearing in my apache logs? We're seeing the exact same thing on one of our Debian VPS servers - with one big difference, the regularity ...
0
votes
1answer
52 views

Network attack on dedicated server [duplicate]

I am using a dedicated server hosting for one of my project. I got a mail from my server provider that their monitoring system noticed a network scan (or network attack) from an IP address. The ...
0
votes
1answer
95 views

What is maximum legitimate SYN traffic rate

Recently my server gets syn flood attack. I use hitcount limitation, but I wonder what is the maximum rate of legitimate syn traffic for a single user IP. The source-IP based rule I use is blow; ...
2
votes
0answers
37 views

How to set permissions for www/dir and make sure no security threats arise

I've a peculiar situation. I've VPS that I use for my own projects. A friend of mine asked me to host his wordpress blog. Now I've setup my VPS very straightforward, all projects are under /www and ...
1
vote
1answer
193 views

How to read sFlow?

We currently have a very large outbound DDOS Attack coming from one of our machines which is on a Brocade switch and monitored by PRTG. I am looking at the sFlow v5 8 sensor and see Top Talkers and ...
0
votes
2answers
279 views

How can I decipher this HTTP PHP-request?

On my server I have serious HTTP an SSH attacks running. Most of them are brute force password checks or attemps of /etc/passwd retrievals. But some of them are trying to start the bash via plugin ...
-1
votes
2answers
146 views

Should I suspicious of this behaviour? [closed]

My website users have perceived that sometimes the server performance is not as it used to be (basically they say that a page that normally loads immediately, could take more than 3 seconds now). This ...
-2
votes
1answer
499 views

I see my full site at another domain [duplicate]

Today I found one of my website fully being displayed at another domain that is not mine. Is this some kind of DNS hack or what is the purpose of these actions ? Because I seen this before, few years ...
0
votes
1answer
174 views

How to expose securely a Node.js/Express server into the real world?

Essentially I would like to know what the title suggests. Node.js/Express is nice. However, node is a fairly recent thing and hence there may be security risks by exposing the server to the real ...
0
votes
1answer
481 views

Login failed for user 'sa'. … [CLIENT: 59.48.47.215]

I have an Amazon EC2 instance and i don't have anything running on it yet but my event log is full of below error "Login failed for user 'sa'. Reason: An attempt to login using SQL authentication ...
1
vote
0answers
351 views

How To Protect Tomcat 7 Against Slowloris Attack

I'm using Apache Tomcat 7 to run my webapp on Linux. I scanned it by Acunetix and it's telling me that my webapp is vulnerable to "Slow HTTP Denial of Service Attack". How can I protect it? Acunetix ...
1
vote
1answer
2k views

What does this Apache access_log entry mean?

68.96.87.214 - - [07/Aug/2013:21:29:25 +0000] "GET /HNAP1/ HTTP/1.1" 403 501 "*************" "Mozilla/4.0 (compatible; Opera/3.0; Windows 4.10) 3.51 [en]" 177.47.105.41 - - [07/Aug/2013:21:57:26 ...
-4
votes
1answer
138 views

How to protect against in-RAM attacks

Since hosting providers are constantly under attack from hackers, encryption of the entire file system (the entire server) with tools like www.truecrypt.org seems like an absolute must to me, if you ...
0
votes
1answer
64 views

Are empty HTTP requests malicious?

I have seen multiple empty http request log entries from Apache: HOST:443 REMOTEIP - - [DATA AND TIME] "-" SIZE SIZE "-" "-" Are these malicious attacks, or some misconfiguration on my side?
0
votes
1answer
407 views

Tracking anonymous e-mail threat

A user spoofed/sent an email from http://emkei.cz/ with a very serious threat. Is it possible to trace this back or are we SOL? There wasn't much in the email headers other than that it came from ...
0
votes
3answers
854 views

POP / IMAP server under attack : what risks and how to secure?

Since yesterday (7am), our POP server is under a dictionnary attack : this is what I found in /var/log/mail.log : Mar 26 10:31:36 serv pop3d: LOGIN FAILED, user=monday, ip=[::ffff:91.121.**.***] Mar ...
0
votes
1answer
280 views

How protect from DDOS attack? [closed]

I have many requests with refferer like alexa.com google.com and etc. to main and couple another pages of site. Line from access.log 109.172.15.39 - - [11/Jan/2013:02:30:30 +0400] "GET ...
0
votes
1answer
523 views

Netscan detected from host [duplicate]

Possible Duplicate: My server’s been hacked EMERGENCY Portscan attacks from somewhere I am using Hetzner's dedicated servers. Today I have got a message: We have received information ...
1
vote
1answer
90 views

Block IPs if they access a resource

I own a server that it's costantly being attacked by scripts (that try to access to phpMyAdmin's setup file's and stuff like this). I've heard that many people get this kinds of attacks, but I'm ...
2
votes
1answer
461 views

What sort of attack URL is this?

I set up a website with my own custom PHP code. It appears that people from places like Ukraine are trying to hack it. They're trying a bunch of odd accesses, seemingly to detect what PHP files I've ...
6
votes
4answers
2k views

How to stop a ICMP attack?

We are under a heavy icmp flood attack. Tcpdump shows the result below. Altough we have blocked ICMP with iptables tcpdump still prints icmp packets. I've also attached iptables configuration and ...
1
vote
2answers
231 views

I got some message about suspended site, which I have to debug, how do I proceed? [duplicate]

Possible Duplicate: My server's been hacked EMERGENCY The hosting company supplied an email to its client and the client wanted some help from me. the message states: Any items listed ...
0
votes
2answers
1k views

Reverse Proxy - should it be a different technology stack?

Got a skeptical question about a reverse proxy setup I'm considering. I've currently got a pair of load balanced application servers in the DMZ (S1,S2 in figure below). These accept inbound requests ...
1
vote
1answer
155 views

Is it normal to collapse VPS CPU with this script?

This is the script, it comes with mod_evasive: #!/usr/bin/perl #test.pl: small script to test mod_dosevasive's effectiveness use IO::Socket; use strict; for(0..100) { my($response); ...
1
vote
4answers
812 views

Solution for DDOS [duplicate]

My server is under DDoS attacks. I see my access log and get something: 968966 93-97-53-41.zone5.bethere.co.uk - - [27/Jul/2011:12:13:58 +0700] "GET /forum/forum.php HTTP/1.1" 200 91231 "-" ...
1
vote
2answers
1k views

Ping O' Death and iptables

Is there a simple rule that can be written to stop a ping o' death with iptables?
0
votes
3answers
403 views

avoid people running “stress tests” / attacks on our server (CentOS + Apache)

today we ran apachebench on our server to stress test it. Of course, our system peaked and disk I/O was massive. Can we avoid that other people run such "tests" or some sort of attack to stress our ...
2
votes
4answers
955 views

Server FTP attack from multiple IP addresses spanning 5 countries - how can this be?

I recently had an FTP attack where 3 files were copied into public HTML directory of my domain. (It looks like the FTP password was compromised, but I'm still investigating this.) The strange thing is ...
0
votes
1answer
167 views

Any way to stop people from img “framing” your site?

Someone was trying to get cute with me, by "iframeing" my search result page via an IMG tag with 0 width and 0 height, in hopes of killing my server resources. My searches are cached, so it doesn't do ...
0
votes
1answer
410 views

How Do I Secure WordPress Blogs Against Elemento_pcx Exploit?

I have a client who has several WordPress 2.9.2 blogs that he hosts. They are getting a deface kind of hack with the Elemento_pcx exploit somehow. It drops these files in the root folder of the blog: ...
2
votes
4answers
374 views

Website attacked with a hidden iframe (q5x.ru)

A website of mine has recently been infected with some sort of attack that involved injecting a hidden iframe, and it's source was from a site q5x.ru (do not link). A Google search didn't help me in ...