Black Basta Ransomware Operators Expand Their Attack Arsenal With QakBot Trojan and PrintNightmare Exploit By Kenneth Adrian Apostol, Paolo Ronniel Labrador, Mirah Manlapig, James Panlilio, Emmanuel Panopio, John Kenneth Reyes, Melvin Singwa ( words) Published: 2022-06-30 · Archived: 2026-04-06 00:33:44 UTC Ransomware We look into a recent attack orchestrated by the Black Basta ransomware group that used the banking trojan QakBot as a means of entry and movement and took advantage of the PrintNightmare vulnerability to perform privileged file operations. By: Kenneth Adrian Apostol, Paolo Ronniel Labrador, Mirah Manlapig, James Panlilio, Emmanuel Panopio, John Kenneth Reyes, Melvin Singwa Jun 30, 2022 Read time: 4 min (955 words) Save to Folio Since it became operational in April, Black Bastaopen on a new tab has garnered notoriety for its recent attacks on 50 organizations around the worldopen on a new tab and its use of double extortionopen on a new tab, a modern ransomware tactic in which attackers encrypt confidential data and threaten to leak it if their demands are not met. The emerging ransomwareopen on a new tab group has continued to improve its attacks: We recently caught it using the banking trojan QakBotopen on a new tab as a means of entry and movement, and taking advantage of the PrintNightmare vulnerability (CVE-2021-34527)open on a new tab to perform privileged file operations. In the case of a Trend Micro customer, its system was infected with Black Basta ransomware that was deployed by QakBot (Figure 1). This behavior is typical of the QakBot malware family, which has served as a key enabler of ransomware families like MegaCortex, PwndLockerm, Egregor, ProLock, and REvil (aka Sodinokibi)open on a new tab. QakBot, which was discovered in 2007, is known for its infiltration capabilities and has been used as a “malware-installation-as-a-service” for various campaigns. Over the years, this banking trojan has become increasingly sophisticated, as evidenced by its exploitation of a newly disclosed Microsoft zero-day vulnerability known as Follina (CVE-2022-30190)open on a new tab. Figure 1. A timeline of the files detected on the infected machine QakBot’s infection chain QakBot is distributed using spear-phishing emails (Figure 2) that contain Excel files with Excel 4.0 macros. The emails entice the recipient to enable macros, which download and execute the QakBot DLL files (Figures 3 and 4). The https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 1 of 7 downloaded QakBot DLL is dropped onto a specific file path and file name, and is executed via regsvr32.exe (Figure 5). The QakBot DLL performs process injection using explorer.exe (Figure 6), after which the injected Explorer process creates a scheduled task to maintain the malware’s initial foothold in the infected system (Figure 7). Figure 2. The infection chain from the point of entry to the Black Basta ransomware payload Figure 3. Instructions in the Excel file used by QakBot to lure a potential victim into enabling Excel 4.0 macros https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 2 of 7 Figure 4. The malicious URL used to download the QakBot malware Figure 5. The downloaded QakBot malware dropped onto a specific file path and file name Figure 6. The explorer.exe process used in process injection Figure 7. The scheduled task created by QakBot Once QakBot is installed in a system, it proceeds to download and drop the other components in the infection chain, beginning with the Cobeacon backdoor. We have observed the execution of Cobeacon using a fileless PowerShell script with multiple layers of obfuscation (Figures 8 to 11). The Base64-encoded shellcode of the installed Cobeacon establishes and names a pipe for communication (Figure 12) that is possibly used for exfiltration purposes once information has been collected from a targeted system. The Black Basta ransomware group posts this information on its leak sites if the victim does not pay the ransom. Figure 8. Cobeacon’s first layer of obfuscation, a Base64-encoded PowerShell command Figure 9. Cobeacon’s second layer of obfuscation, the loading and reading of an archive file in memory https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 3 of 7 Figure 10. Cobeacon’s third layer of obfuscation, the decoded script for running the Base64-encoded shellcode Figure 11. Disassembly of the decoded shellcode https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 4 of 7 Figure 12. Shellcode containing the named pipe for communication PrintNightmare and Coroxy Upon further analysis of the system that was affected by Black Basta, we found evidence that points to the ransomware group’s exploitation of the PrintNightmare vulnerabilityopen on a new tab. Exploiting this vulnerability, Black Basta abused the Windows Print Spooler Service or spoolsv.exe to drop its payload, spider.dll, and perform privileged file operations. It also exploited the vulnerability to execute another file in the affected system, but samples of this file were no longer available in the system. Additionally, our investigation found that the ransomware actors used the Coroxy backdoor. They used Coroxy in conjunction with the abuse of the computer networking utility tool Netcat to move laterally across the network. Once the attackers gained a wide foothold in the network, they executed the Black Basta ransomware, whose infection process we explained in more detail in a previous blog postopen on a new tab. Thwarting phishing attempts Spear phishing is a common precursor to ransomware infection. Organizations can protect their data from threats that spread through emails by adhering to best practices such as: Ensuring that macros are disabled in Microsoft Office applications. Verifying an email’s sender and content before opening or downloading any attachments. Hovering the pointer over embedded links to show the links’ full addresses. Being wary of telltale signs of malicious intent, including unfamiliar email addresses, mismatched email and sender names, and spoofed company emails. Businesses and their employees can safeguard sensitive company data from email-borne ransomware threats like Black Basta by turning to endpoint solutions such as Trend Micro’s Smart Protection Suitesproducts and Worry-Free Business Securityworry free services suites solutions, which are equipped with behavior-monitoring capabilities that are able to detect malicious files, scripts, and messages, and block all related malicious URLs. Trend Micro™ Deep Discovery™products also has a layer for email inspectionproducts that protects businesses by detecting any malicious attachments and URLs. Multilayered detection and response solutions like the Trend Micro Vision One™products platform provides companies with greater visibility across multiple layers — like email, endpoints, servers, cloud workloads, and networks — to look out for suspicious behavior in their systems and block malicious components early, mitigating the risk of ransomware infection.  Indicators of compromise Hashes SHA-256 Trend Micro detection 01fafd51bb42f032b08b1c30130b963843fea0493500e871d6a6a87e555c7bac Ransom.Win32.BLACKBASTA.YXCEP 72a48f8592d89eb53a18821a54fd791298fcc0b3fc6bf9397fd71498527e7c0e Trojan.X97M.QAKBOT.YXCFH https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 5 of 7 580ce8b7f5a373d5d7fbfbfef5204d18b8f9407b0c2cbf3bcae808f4d642076a Backdoor.Win32.COROXY.YACEKT 130af6a91aa9ecbf70456a0bee87f947bf4ddc2d2775459e3feac563007e1aed Trojan.Win64.QUAKNIGHTMARE.YACEJT c7eb0facf612dbf76f5e3fe665fe0c4bfed48d94edc872952a065139720e3166 TrojanSpy.Win32.QAKBOT.YXCEEZ ffa7f0e7a2bb0edf4b7785b99aa39c96d1fe891eb6f89a65d76a57ff04ef17ab TrojanSpy.Win32.QAKBOT.YACEJT 2083e4c80ade0ac39365365d55b243dbac2a1b5c3a700aad383c110db073f2d9 TrojanSpy.Win32.QAKBOT.YACEJT 1e7174f3d815c12562c5c1978af6abbf2d81df16a8724d2a1cf596065f3f15a2 TrojanSpy.Win32.QAKBOT.YACEJT 2d906ed670b24ebc3f6c54e7be5a32096058388886737b1541d793ff5d134ccb TrojanSpy.Win32.QAKBOT.YACEJT 72fde47d3895b134784b19d664897b36ea6b9b8e19a602a0aaff5183c4ec7d24 TrojanSpy.Win32.QAKBOT.YACEJT 2e890fd02c3e0d85d69c698853494c1bab381c38d5272baa2a3c2bc0387684c1 TrojanSpy.Win32.QAKBOT.YACEJT c9df12fbfcae3ac0894c1234e376945bc8268acdc20de72c8dd16bf1fab6bb70 Ransom.Win32.BLACKBASTA.YACEJ 8882186bace198be59147bcabae6643d2a7a490ad08298a4428a8e64e24907ad Trojan.Win32.BLACKBASTA.YXCEJ 0e2b951ae07183c44416ff6fa8d7b8924348701efa75dd3cb14c708537471d27 Trojan.Win32.BLACKBASTA.YXCEJ 0d3af630c03350935a902d0cce4dc64c5cfff8012b2ffc2f4ce5040fdec524ed Trojan.Win32.BLACKBASTA.YXCEJ df35b45ed34eaca32cda6089acbfe638d2d1a3593d74019b6717afed90dbd5f8 Trojan.Win32.BLACKBASTA.YXCEJ 3fe73707c2042fefe56d0f277a3c91b5c943393cf42c2a4c683867d6866116fc Trojan.Win32.BLACKBASTA.YXCEJ 433e572e880c40c7b73f9b4befbe81a5dca1185ba2b2c58b59a5a10a501d4236 Ransom.Win32.BLACKBASTA.A.note https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 6 of 7 c4683097a2615252eeddab06c54872efb14c2ee2da8997b1c73844e582081a79 PUA.Win32.Netcat.B URLs 24[.]178[.]196[.]44:2222 37[.]186[.]54[.]185:995 39[.]44[.]144[.]182:995 45[.]63[.]1[.]88:443 46[.]176[.]222[.]241:995 47[.]23[.]89[.]126:995 72[.]12[.]115[.]15:22 72[.]76[.]94[.]52:443 72[.]252[.]157[.]37:995 72[.]252[.]157[.]212:990 73[.]67[.]152[.]122:2222 75[.]99[.]168[.]46:61201 103[.]246[.]242[.]230:443 113[.]89[.]5[.]177:995 148[.]0[.]57[.]82:443 167[.]86[.]165[.]191:443 173[.]174[.]216[.]185:443 180[.]129[.]20[.]53:995 190[.]252[.]242[.]214:443 217[.]128[.]122[.]16:2222 elblogdeloscachanillas[.]com[.]mx/S3sY8RQ10/Ophn[.]png lalualex[.]com/ApUUBp1ccd/Ophn[.]png lizety[.]com/mJYvpo2xhx/Ophn[.]png Tags Source: https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html https://www.trendmicro.com/en_us/research/22/f/black-basta-ransomware-operators-expand-their-attack-arsenal-wit.html Page 7 of 7