# MAR-10265965-2.v1 – North Korean Trojan: SLICKSHOES **us-cert.gov/ncas/analysis-reports/ar20-045b** ## Notification This report is provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of an information contained herein. The DHS does not endorse any commercial product or service referenced in this bulletin or otherwise. This document is marked TLP:WHITE--Disclosure is not limited. Sources may use TLP:WHITE when information carries minimal or no foreseeab accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distribute For more information on the Traffic Light Protocol (TLP), see http://www.us-cert.gov/tlp. ## Summary Description This Malware Analysis Report (MAR) is the result of analytic efforts between Department of Homeland Security (DHS), the Federal Bureau of Inve the Department of Defense (DoD). Working with U.S. Government partners, DHS, FBI, and DoD identified Trojan malware variants used by the N government. This malware variant has been identified as SLICKSHOES. The U.S. Government refers to malicious cyber activity by the North Kore HIDDEN COBRA. For more information on HIDDEN COBRA activity, visit https[:]//www[.]us-cert.gov/hiddencobra. DHS, FBI, and DoD are distributing this MAR to enable network defense and reduce exposure to North Korean government malicious cyber activi This MAR includes malware descriptions related to HIDDEN COBRA, suggested response actions and recommended mitigation techniques. Use should flag activity associated with the malware and report the activity to the Cybersecurity and Infrastructure Security Agency (CISA) or the FBI C (CyWatch), and give the activity the highest priority for enhanced mitigation. This sample is a Themida-packed dropper that decodes and drops a file "C:\Windows\Web\taskenc.exe" which is a Themida-packed beaconing im beaconing implant does not execute the dropped file nor does it schedule any tasks to run the malware. The dropped beaconing implant uses an encoding algorithm and is capable of many features including conducting system surveys, file upload/download, process and command execution captures. [For a downloadable copy of IOCs, see MAR-10265965-2.v1.stix.](https://www.us-cert.gov/sites/default/files/publications/MAR-10265965-2.v1.stix.xml) Submitted Files (1) fdb87add07d3459c43cfa88744656f6c00effa6b7ec92cb7c8b911d233aeb4ac (CCA9FBB11C194FC53015185B741887...) IPs (1) 188.165.37.168 ## Findings **fdb87add07d3459c43cfa88744656f6c00effa6b7ec92cb7c8b911d233aeb4ac** Tags emotettrojan Details **Name** CCA9FBB11C194FC53015185B741887A8 **Size** 3133440 bytes **Type** PE32 executable (GUI) Intel 80386, for MS Windows **MD5** cca9fbb11c194fc53015185b741887a8 **SHA1** 9e7bf03a607558dafe146907db28d77fda81be22 **SHA256** fdb87add07d3459c43cfa88744656f6c00effa6b7ec92cb7c8b911d233aeb4ac **SHA512** a1d1747dbc96c14b45f345679c0f7ba38186458f4992eecf382dd0af6391b4224c1b487431d681f5ffd052839f2901bc6203ea81c3235efc **ssdeep** 49152:bbcROoCHuumCvGyQwNr6Ljvhg1J/4fxcBhmdSP8sWNRy8kLn3o1Dn:jVHaaGyQG6npcJ4xcD5d2Ry8kDo **Entropy** 7.968879 Antivirus **Ahnlab** Trojan/Win32.Agent **Antiy** Trojan/Win32.Casdet **Avira** TR/Crypt.TPM.Gen **BitDefender** Gen:Variant.Barys.1619 ----- **ClamAV** Win.Trojan.Agent-7376504-0 **Cyren** W32/Trojan.QBAU-3559 **ESET** a variant of Win32/Packed.Themida.AOO trojan **Emsisoft** Gen:Variant.Barys.1619 (B) **Ikarus** Trojan.Win32.Themida **K7** Trojan ( 0040f4ef1 ) **McAfee** Trojan-Themida **Microsoft Security Essentials** Trojan:Win32/Emotet **NANOAV** Trojan.Win32.TPM.ggaakh **Sophos** Troj/Agent-BCXR **Symantec** Trojan Horse **VirusBlokAda** Trojan.Wacatac **Zillya!** Trojan.Themida.Win32.3185 YARA Rules No matches found. ssdeep Matches No matches found. PE Metadata **Compile Date** 2018-02-26 20:08:54-05:00 **Import Hash** baa93d47220682c04d92f7797d9224ce PE Sections **MD5** **Name** **Raw Size** **Entropy** 0de0ceb73fba415dc20a730f628429a6 header 4096 0.816628 74520bd2f6bb3211bd82b6f9547ff207 1572864 7.979303 32762b0a8ae1347aebaba811505cadcf .rsrc 49152 4.290489 79cf217f58f3178dafbfe532c01ef5c4 .idata 512 1.308723 f0347e7e1ac9efb817c55b3ba9e5bf2d 512 0.264678 4fb94c6713c62a51c1b230a2bc033fac suylcrzz 1505792 7.954736 81610ae95a418f6ef9ef042b37a26c4a ajqluhke 512 3.110274 Relationships fdb87add07... Connected_To 188.165.37.168 Description This sample is a Themida-packed dropper that decodes and drops an embedded file (MD5: B57DB76CC1C0175C4F18EA059D9E2AB2 / SHA25 7250ccf4fad4d83d087a03d0dd67d1c00bf6cb8e7fa718140507a9d5ffa50b54) to C:\Windows\Web\taskenc.exe. This dropper does not execute the create any auto-run keys or scheduled tasks to execute it. The dropped file (taskenc.exe) is a Themida-packed beaconing implant with RAT functionality. The implant beacons to a hardcoded IP (188.165.3 hardcoded TCP port 80 every 60 seconds. The initial beacon contains the string “ApolloZeus” as well as victim information, including OS version, address. All traffic, including the beacon, is encoded with an indigenous encoding algorithm. Due to the way the implant decodes the hardcoded s place in memory, the first beacon contains the string in plaintext, the second beacon will contain the string encoded, and so on. This is probably u oversight by the developers. --Begin Packet Format- [8 Bytes data length][2Byte Opcode][data] --End Packet Format- ----- g OS Version User name IP address --End Victim Information- A Python3 script for decoding the traffic is displayed below: --Begin Python3 Script-def decode(enc): dec = b’’ key1 = 0x49; key2 = 0x1310a024; key3 = 0xa323da32; for e in enc: dec += chr((ord(e) ^ key3 ^ key1) & 0xff) tmp1 = key3 >> 8 key1 = (key2>>0x10) & (key2>>8) & key2 ^ (key3>>0x10) & tmp1 ^ key3 & key1 ^ (key3>>0x18); tmp2 = key3 * 2 ^ key3; key3 = key2 << 0x18 | key3 >> 8; key2 = (tmp2 & 0x1fe) << 0x16 | key2 >> 8; return dec --End Python3 Script-Screenshots **Figure 1 - Implant Functionality.** **188.165.37.168** Ports 80 TCP Relationships 188.165.37.168 Connected_From fdb87add07d3459c43cfa88744656f6c00effa6b7ec92cb7c8b911d233aeb4ac Description Hardcoded C2 address used in implant. ## Relationship Summary fdb87add07... Connected_To 188.165.37.168 188.165.37.168 Connected_From fdb87add07d3459c43cfa88744656f6c00effa6b7ec92cb7c8b911d233aeb4ac ## Recommendations CISA recommends that users and administrators consider using the following best practices to strengthen the security posture of their organizatio configuration changes should be reviewed by system owners and administrators prior to implementation to avoid unwanted impacts. Maintain up-to-date antivirus signatures and engines. Keep operating system patches up-to-date. Disable File and Printer sharing services. If these services are required, use strong passwords or Active Directory authentication. Restrict users' ability (permissions) to install and run unwanted software applications. Do not add users to the local administrators group unl Enforce a strong password policy and implement regular password changes. Exercise caution when opening e-mail attachments even if the attachment is expected and the sender appears to be known. Enable a personal firewall on agency workstations, configured to deny unsolicited connection requests. Disable unnecessary services on agency workstations and servers. Scan for and remove suspicious e-mail attachments; ensure the scanned attachment is its "true file type" (i.e., the extension matches the file Monitor users' web browsing habits; restrict access to sites with unfavorable content. Exercise caution when using removable media (e.g., USB thumb drives, external drives, CDs, etc.). Scan all software downloaded from the Internet prior to executing. Maintain situational awareness of the latest threats and implement appropriate Access Control Lists (ACLs). ----- p g gy ( ) p **"Guide to Malware Incident Prevention & Handling for Desktops and Laptops".** ## Contact Information CISA continuously strives to improve its products and services. You can help by answering a very short series of questions about this product at t [https://us-cert.gov/forms/feedback/](https://us-cert.gov/forms/feedback/) ## Document FAQ **What is a MIFR? A Malware Initial Findings Report (MIFR) is intended to provide organizations with malware analysis in a timely manner. In most** will provide initial indicators for computer and network defense. To request additional analysis, please contact CISA and provide information regar desired analysis. **What is a MAR? A Malware Analysis Report (MAR) is intended to provide organizations with more detailed malware analysis acquired via manua** engineering. To request additional analysis, please contact CISA and provide information regarding the level of desired analysis. **Can I edit this document? This document is not to be edited in any way by recipients. All comments or questions related to this document should** [CISA at 1-888-282-0870 or soc@us-cert.gov.](http://10.10.0.46/mailto:soc@us-cert.gov) **Can I submit malware to CISA? Malware samples can be submitted via three methods:** Web: [https://malware.us-cert.gov](https://malware.us-cert.gov/) E-Mail: [submit@malware.us-cert.gov](http://10.10.0.46/mailto:submit@malware.us-cert.gov) FTP: ftp.malware.us-cert.gov (anonymous) CISA encourages you to report any suspicious activity, including cybersecurity incidents, possible malicious code, software vulnerabilities, and ph [Reporting forms can be found on CISA's homepage at www.us-cert.gov.](http://www.us-cert.gov/) ## Revisions February 14, 2020: Initial Version [This product is provided subject to this Notification and this](https://www.us-cert.gov/privacy/notification) [Privacy & Use policy.](https://www.dhs.gov/privacy-policy) **Please share your thoughts.** [We recently updated our anonymous product survey; we'd welcome your feedback.](https://www.surveymonkey.com/r/CISA-cyber-survey?product=https://us-cert.cisa.gov/ncas/analysis-reports/ar20-045b) -----