SMB in the limelight – WannaCry and more!

Days before WannaCry came into the spotlight, there were already some other ransomware and malware taking advantage of the SMB exploit (published under the codename ETERNALBLUE/DOUBLEPULSAR) following shadow brokers dump (NSA exploit targeting windows file sharing protocol). So far, WannaCry ransomware has infected more than 150 countries causing widespread panic. Although WannaCry distribution may have been stopped, the widespread of ransomware and similar malware distribution has not stopped yet.

Other Variants

UIWIX is an entirely new variant and has also been spotted in the wild. Like WannaCry, this ransomware program is also built under ETERNABLUE. It has ability to infect machines without writing files to permanent storage and hence, making it extremely harder to detect through conventional forensics. This ransomware renames files with ‘.uiwix’ extension and drops a text file called ’_DECODE_FILES.txt’ which contains requirements for decryption and payment address and mode of payment. Uiwix however poses an even bigger threat than WannaCry ransomware since it does not include any kill switch domains.
 

Another program using the same SMB vulnerability to exploit the system using EternalBlue and DoublePulsar is Adylkuzz. Adylkuzz exploits the SMB vulnerability to mine an obscure cryptocurrency called Monero.

Basically, Monero is a cryptocurrency similar to the Bitcoin but with enhanced anonymity capabilities. A major of underground website known to sell drugs, stolen credit cards and counterfeit items make use of monero. However, unlike WannaCry, Adylkuzz does not have the ability to self-propagate.

It has been found that Adylkuzz started exploiting the same vulnerability somewhere between 24th April and 2nd May i.e. weeks before WannaCry came into the scene. It infects the system taking an advantage of SMB vulnerability and shuts down SMB networking for further infection of the system with other malwares including WannaCry ransomware worm, detects the public IP address of the system, downloads the mining instructions, cryptominer and other cleaner tools. Therefore, we can easily predict that there are huge number of systems being infected with this very malware than that of WannaCry ransomware worm. Adylkuzz did not caused the same chaos as that of WannaCry since it was not shutting down computers or was not sending some ransom notes, all it did was perform Monero mining operation in the background. Although it is not catastrophic enough to raise an alarm and remained undected and hidden until the WannaCry came into the limelight gaining much more public attention.

Who is behind the current attack?
It has been found that WannaCry’s code shares some portion of the code to the Lazarus APT group who was responsible heavily for the Sony Wiper attack (Sony Pictures Entertainment being hacked using wiper malware), the Bangladesh bank heist ($81 million heist from SWIFT network using Dridex malware) and the DarkSeoul operations (Backdoor Trojan, dubbed as Duuzer, Brambul and Joanap malware targeting south Korean organizations, institutions and industries). Lazarus APT group was found to have conducted multiple attacks worldwide and was found to have a direct link between Bluenoroff and North Korea. So, there could be a possible clue that North Korea could probably be behind the current WannaCry attack. However, it is still too early to determine who exactly is behind this attack since, the repetition of the code could also be a false flag.

Final Words
It is therefore, highly recommended that you update your systems for MS17-010 and if you do not use SMB then it is also recommended that you disable the SMB version one.

To disable SMB follow the following steps:

1. Open Control Panel.
2. Click Programs.
3. Click Turn Windows features on or off (under the Programs).
4. Make sure that your ‘SMB 1.0/CIFS File Sharing Support’ is not ticked.

If you are a PowerShell user make sure that you disable SMB version one by typing the following command with administrator privilege:

Set-ItemProperty -Path “HKLM:\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters” SMB1 -Value 0 -Force

That's it, you are protected for now.

Oops! Your important files are encrypted. - Ransomware (WannaCry in Nepal?)

There was nothing new with these words. We have had heard a lot about ransomware like Cryptowall, Jigsaw, Cerber, Cryptolocker, Teslacrypt, Locky and more. Displaying a nasty message on a desktop, asking for ransom and encrypting almost all files on the system. But this very sentence (Oops! Your important files are encrypted.) and this variant of ransomware was a complete different than others. It was more of a ransomware worm. Cyber criminals had started a new sophisticated cyber-attacking campaign starting Friday (12th May 2017). I am sure, this Monday (15th May) was definitely, the most hectic day for most of the IT guys, fixing the infected systems and issuing the patch and maybe paying ransom ($300 or $600) was the last option too.

We have heard stories of Google docs phishing attack campaign spread like a worm about two weeks back. And now, the most deadly ransomware worm known as WannaCrypt, WannaCry, WannaCrypt0r, WCryptor or WCRY which started attack on the internet, infecting thousands of devices and affecting more than hundred countries. Russia, Ukraine, India were among the top victims of this recent attack as reported by Kaspersky.

Figure shows countries affected with WannyCry ransomware

The ransomware came out on Friday causing an extremely chaotic situation to the whole world where targets including extremely high profile organizations including government forces, railway stations, hospitals, universities and many public and private organizations including organizations like Russian Interior Ministry in Russia, German’s Deutsche Bahn in Germany, FedEx in US, National Health Service (NHS) in UK, Renault in France, Portugal Telecom in Portugal, Telefonica in Spain, Andhra Pradesh Police in India and others who were the serious victims of recent cyber-attack. This kind of large scale cyber-attacks could be the beginning of new trend for organized cyber criminals. As workdays started on Monday, the number of affected companies, communities and people could still rise. As seen today, reported by China’s news agency around thirty thousand companies have been hit on China and more than two thousand computers have been infected in Japan and the number is still on rise. 

NHS was protected with Sophos (Seems like technologies cannot be trusted? Since, Security is not a product, it's a continuous process)

While working around, I also came to know that, some high profile ISP’s and private organizations of Nepal could be the victims of this ransomware attack campaign. Organizations like Nepal Telecom, Subisu, Worldlink, OTEL, Kantipur Media Group and other more organizations were found to be highly vulnerable to WannaCry Ransomware attack or say, EternalBlue and DoublePulsar exploit attack.

All Windows versions before Windows 10 are vulnerable to ‘WannaCry’ if not patched for MS-17-010. The ransomware worm makes use of EternalBlue MS17-010 to propagate.

EternalBlue, sometimes stylized as ETERNALBLUE, is an exploit developed by the U.S. National Security Agency (NSA). It was released by the Shadow Brokers hacker group on April 14, 2017.

EternalBlue exploits a vulnerability in Microsoft's implementation of the Server Message Block (SMB) protocol. The attackers were able to take advantage of this very vulnerability, exploit and propagate around the globe in a form of ransomware worm.

After the chaotic spread of this ransomware worm, Microsoft also came with an update for Windows XP although End of Life (EOL) for Windows XP was on 8th of April 2014.

But, as of now, the ransomware worm is down, meaning that a researcher and also a blogger by the name MalwareTech has slowed down the cyber-attack by simply registering a domain iuqerfsodp9ifjaposdfjhgosurijfaewrwergwea[.]com, under a name of ‘Botnet Sinkhole’ which acted as a kill switch for the ransomware since the working mechanism of the ransomware was to search for the mentioned domain and if the domain was up, the attack would stop or else continue propagating. However, another researcher (Matthieu Suiche) has also confirmed that he found a new WannaCry variant with a different kill switch and registered new domain ifferfsodp9ifjaposdfjhgosurijfaewrwergwea[.]com However multiple security researches have claimed that there are more samples of the ransomware with different kill-swith and even without any kill-switch function.

As of 14th May, the total of $33,319.59 has been paid. Three bitcoin address were hardcoded into the ransomware itself

(13AM4VW2dhxYgXeQepoHkHSQuy6NgaEb94,12t9YDPgwueZ9NyMgw519p7AA8isjr6SMw, 115p7UMMngoj1pMvkpHijcRdfJNXj6LrLn)

So far, these are the C&C centers found from various sources:

gx7ekbenv2riucmf.onion
57g7spgrzlojinas.onion
xxlvbrloxvriy2c5.onion
76jdd2ir2embyv47.onion
cwwnhwhlz52maqm7.onion

C&C IP address found from various sources:

188[.]166[.]23[.]127:443
193[.]23[.]244[.]244:443
2[.]3[.]69[.]209:9001
146[.]0[.]32[.]144:9001
50[.]7[.]161[.]218:9001
217[.]79[.]179[.]77
128[.]31[.]0[.]39
213[.]61[.]66[.]116
212[.]47[.]232[.]237
81[.]30[.]158[.]223
79[.]172[.]193[.]32
89[.]45[.]235[.]21
38[.]229[.]72[.]16
188[.]138[.]33[.]220

The filetypes that it looks to encrypt are:

.doc, .docx, .xls, .xlsx, .ppt, .pptx, .pst, .ost, .msg, .eml, .vsd, .vsdx, .txt, .csv, .rtf, .123, .wks, .wk1, .pdf, .dwg, .onetoc2, .snt, .jpeg, .jpg, .docb, .docm, .dot, .dotm, .dotx, .xlsm, .xlsb, .xlw, .xlt, .xlm, .xlc, .xltx, .xltm, .pptm, .pot, .pps, .ppsm, .ppsx, .ppam, .potx, .potm, .edb, .hwp, .602, .sxi, .sti, .sldx, .sldm, .sldm, .vdi, .vmdk, .vmx, .gpg, .aes, .ARC, .PAQ, .bz2, .tbk, .bak, .tar, .tgz, .gz, .7z, .rar, .zip, .backup, .iso, .vcd, .bmp, .png, .gif, .raw, .cgm, .tif, .tiff, .nef, .psd, .ai, .svg, .djvu, .m4u, .m3u, .mid, .wma, .flv, .3g2, .mkv, .3gp, .mp4, .mov, .avi, .asf, .mpeg, .vob, .mpg, .wmv, .fla, .swf, .wav, .mp3, .sh, .class, .jar, .java, .rb, .asp, .php, .jsp, .brd, .sch, .dch, .dip, .pl, .vb, .vbs, .ps1, .bat, .cmd, .js, .asm, .h, .pas, .cpp, .c, .cs, .suo, .sln, .ldf, .mdf, .ibd, .myi, .myd, .frm, .odb, .dbf, .db, .mdb, .accdb, .sql, .sqlitedb, .sqlite3, .asc, .lay6, .lay, .mml, .sxm, .otg, .odg, .uop, .std, .sxd, .otp, .odp, .wb2, .slk, .dif, .stc, .sxc, .ots, .ods, .3dm, .max, .3ds, .uot, .stw, .sxw, .ott, .odt, .pem, .p12, .csr, .crt, .key, .pfx, .der


How to be safe?

• For now, ensure that all Windows-based systems are fully patched. At a very minimum, ensure Microsoft bulletin MS17-010 has been applied.
• If your organization has SMB publicly accessible via the internet (ports 139, 445) should immediately be blocked for inbound traffics.
• If your organization is using snort then apply snort 42329-42332, 42340, 41978 rules immediately

These kinds of attacks are also more likely to happen in future, it all starts with just one click of yours so stay safe, stay secure.

At least follow the bellow mentioned points:

• First and foremost, be sure to back up your most important files on a regular basis.
• Personalize your anti-spam settings the right way.
• Refrain from opening attachments that look suspicious.
• Think twice before clicking.
• Patch and keep your operating system, antivirus, browsers, Adobe Flash Player, Java, and other software up-to-date.
• In the event a suspicious process is spotted on your computer, instantly turn off the Internet connection.
• Keep the Windows Firewall turned on and properly configured at all times.
• Enhance your protection more by setting up additional Firewall protection.
• Adjust your security software to scan compressed or archived files, if this feature is available.
• Consider disabling Windows PowerShell, which is a task automation framework if you do not use it.
• Disable Macros and ActiveX in Microsoft Office components.
• Install a browser add-on to block popups as they can also pose an entry point for ransom Trojan attacks.
• Deactivate AutoPlay.
• Make sure you disable file sharing.
• Disable Remote Service if not in use
• Block known-malicious Tor IP addresses