::Trend Micro Threat Resource Center::

21 April 2016

1 in 6 emails contains a virus: study


After Locky, here comes KePanger, PowerWare and Petya. According to a current analysis by Retarus security experts, 17% of all incoming email messages are blocked due to a suspected virus. The security experts are currently observing a significantly higher incidence of the crypto trojan Locky, as well as new variations. This corresponds to a fivefold rise in comparison with the previous month and can be explained primarily by the large increase in ransomware.

On average, in March, one in six emails sent to mailboxes used for business purposes contained a virus. In total, this means just as many infected messages occurred per hour as occurred per month in 2015 on average.

The analysis by the Retarus experts revealed that this can be explained by the huge rise in the incidence of crypto trojans. Whilst in February only around 3% of all incoming emails were infected, the number of messages filtered in March due to viruses had already risen to 17%. The reason: During this period, numerous additional versions of the virus appeared after the first Locky threat wave.

As crypto trojans can morph their structure quickly and frequently and, as a result, are able to assume the most diverse forms at lightning speed, ransomware is not detected immediately by every virus scanner. Nevertheless, security can be increased using professional cloud services. Specialized email security services access several scanners in parallel, thereby continuously expanding their filter rules, which means they can always offer the latest protection levels. Additional mechanisms, such as a four-level virus scan, also increase the likelihood of identifying and blocking extortion trojans in good time.

Heightened vigilance is essential
To ensure the best possible protection from attacks by Locky and similar ransomware, email users must be highly vigilant. Retarus recommends that users deactivate the automatic execution of embedded macro code in Office programs and that macros should only be activated if they are absolutely essential and where the corresponding documents originate from known sources.

In principle, users should only open email attachments if the sender or the process described in the email is trustworthy. So that potentially affected data can be restored quickly and - wherever possible - without losses, important data should be backed up on a regular basis. Here it should be noted that Locky can also attack external data media if this is permanently connected to the computer.

Caution is also advised in the event of an extremely slow processor response, elevated hard drive activity without a detectable reason, or files with the extension .locky on the hard drive. To close existing gaps in security, the latest versions of virus scanners should always be installed and regular patches performed.

08 April 2016

Blackhat Asia 2016

Glad to be back at this amazing conference. I attended the last one held in 2015, with access to all briefings and the session content are intriguing and scary at the same time.

But as they say, no defense is 100% foolproof. They WILL get in anyhow, it's how long you take to to detect and respond.

Some highlights from Arsenal:

o   CrackMapExec
§  Aims to be a one-stop-shop for pentesting Active Directory environments! Think smbexec on steroids, combining the latest and greatest techniques for AD ownage in a single tool!
§  From enumerating logged on users and spidering SMB shares to executing psexec style attacks, concurrently auto-injecting Mimikatz/Shellcode/DLL's into memory using Powershell, dumping the NTDS.dit, querying and executing commands through MSSQL DB's and more!
§  The biggest improvements over the current tools are:
·         Pure Python script, no external tools required
·         Fully concurrent threading
·         Uses ONLY native WinAPI calls for discovering sessions, users, dumping SAM hashes etc...
·         Opsec safe (no binaries are uploaded to dump clear-text credentials, inject shellcode etc...)
§  Fully open-source and hosted on Github!

o   VirusTotal
§  A free online file and URL scanner that everyone knows.
§  However there are many free features that many users don't know about such as:
·         A free public API for anyone to automate file or URL analysis.
·         IP address and domain reputation. See malware files known to be associated with a particular IP address or domain, and history Passive DNS info
·         Sysinternals, Carbon black, etc. integrations
·         Static analysis of files, structural analysis of many file types (PE, ELF, APK, ZIP, RAR, MACHO, .NET, office, etc)
·         Sandbox dynamic analysis of PE, APK, Apple Mach-O, and applications.
·         ROMS, BIOS, and firmware files
·         SSDEEP, authentihash, imphash, and other similarity indexes
·         Certificate checks on signed files
·         Whitelisting of trusted files

·         Free desktop scanning applications for Windows, MAC, and open source for compilation on linux.

Had a short chat with the developer of CrackMapExec, he mentioned that this tool runs entirely in memory and does not have any footprint. It is basically undetectable, except that the only tell-tale signs of execution would be spikes in the CPU and RAM usage.

Demonstration of CrackMapExec by @byt3bl33d3r 

06 April 2016

GitHub recovers from major outage; cause unknown


GitHub, a frequent target of distributed denial of service (DDoS) attacks, experienced a major outage early Tuesday morning, Eastern Time; however, the software development hosting service tweeted shortly thereafter that it identified the problem and that its online operations were running normally again.

As of press time, it is not publicly known if the outage stemmed from an internal error or from the latest in a series of external cyberattacks against the service. GitHub's site performance was noticeably impacted just this past Mar. 23 following a DDoS assault against the website.

Asked for an update and an explanation of the underlying issue, a member of GitHub's communications department directed SCMagazine.com to its online status page, which showed that from around 4:30 a.m. to 6 a.m. ET, app server availability ostensibly plummeted to zero percent, while response times spiked.

Travis Smith, senior security research engineer at cybersecurity software firm Tripwire, said in a statement emailed to SCMagazine.com. “While a drop in service such as this may be attributed to an operational malfunction internally at GitHub, it can't be ruled out that this was a targeted attack” against not just GitHub, but also “any number of their customers who leverage GitHub's service in production environments.”

GitHub experienced an especially severe DDoS attack in March 2015 — an attack that many researchers have attributed to state-sponsored Chinese hackers.