Guildma / Astaroth
Guildma / Astaroth (canonical dual industry naming reflecting Avast naming Guildma + Cybereason naming Astaroth, confirmed same malware family per Avast Adolf Streda 2019 canonical dual-naming clarification analysis "almost certainly the same malware as that described by Cybereason as Astaroth, but analyzed here in greater detail".
Brazilian-origin highly- modular banking trojan + Remote Access Tool RAT + spyware + password stealer + information stealer active since at least 2015 per Avast estimate that "first versions of Guildma were created in 2015" with module encryption seed unchanged since late 2015) is a Latin American banking trojan operating signature Brazil - Latin America - US + Spain + Portugal global expansion since 2015 with Avast 2019 detected ~155,000 infection attempts (98% still in Brazil but targeting 130 banks + web services including Netflix + Facebook + Amazon + Google Mail globally)
standalone malware platform cluster paralleling grandoreiro + mekotio in Latin American banking trojan operators cell.
Brazilian-origin organized cybercrime attribution via Kaspersky Securelist canonical July 14, 2020 "The Tetrade: Brazilian banking malware goes global" by Fabio Assolini framework classification (Guildma + Javali + Melcoz + Grandoreiro four major Brazilian banking trojan families) + Microsoft Defender ATP Research Team canonical July 9, 2019 fileless Astaroth campaign disclosure ("completely 'lived off the land' throughout a complex attack chain that ran the info-stealing backdoor Astaroth directly in memory" per Microsoft Security Intelligence Twitter @MsftSecIntel) + Cybereason 2019 canonical Astaroth analysis + Cofense PDC September 2018 South American campaign disclosure (~8,000 machines compromised within single week)
cluster-defining fileless + LOLBin tradecraft with signature LOLBin abuse arsenal including WMIC (Windows Management Instrumentation Command-line with /Format parameter for XSL download + JavaScript execution per Microsoft ATP) + BITSAdmin (allowlisted Windows tool for additional module download, relied on for years to avoid detection per Kaspersky) + ExtExport (legitimate utility for malicious DLL loading) + Finger Windows utility (per Tempest SideChannel 2021, Windows utility for remote code execution) + historical aswrundll.exe Avast binary abuse (now blocked per Avast)
cluster-defining NTFS Alternate Data Streams (ADS) payload concealment tradecraft per Kaspersky November 2019 disclosure (payload storage in desktop.ini ADS hides files from Windows Explorer requiring DIR /R command for ADS display)
cluster- defining cloud-hosting C2 abuse including CloudFlare Workers + Amazon AWS + YouTube channels + Facebook pages for payload storage + C2 information concealment per Kaspersky.
DLL Search Order Hijacking malware binary launch + process hollowing inside svchost.exe per Kaspersky.
multi-language phishing tradecraft with Spanish + Portuguese + English spearphishing using LNK + VBS + ZIP + HTML/JavaScript attachments (COVID-19 themed including "Purchase invoice for alcohol gel: Guildma's trick for luring victims" per Kaspersky)
DGA generating ~200+ daily URLs using generic TLDs per Kaspersky newer Guildma 2020 versions.
comprehensive anti-analysis tradecraft (anti-debugging + anti-virtualization + anti-emulation + security tool detection for OllyDbg + WinDbg + Process Hacker + Process Monitor + Wireshark + force machine reboot on detection per Tempest)
comprehensive credential theft including banking credentials via fake pop-up overlays + browser password stores + SSH credentials + email credentials with HTTPS POST exfiltration per Armor.
Tempest SideChannel 2021 additional disclosure of XSS-vulnerable website exploitation as initial payload delivery (~10% of late January 2021 Astaroth campaigns)
Delphi programming language origin signature (typical Latin American banking trojan) with open-source RAT lineage (Delphi Remote Access PC + AmigoRAT + PureRAT) per Avast.
version 140+ continuous development per Avast 2019 + extended targeting Chile + Uruguay + Peru + Ecuador + Colombia + China + Europe per Kaspersky Tetrade framework.
cluster fills the most-fileless- LOLBin-tradecraft position in Latin American banking trojan operators cell.
canonical illustration of fileless + LOLBin abuse + NTFS ADS payload concealment + cloud-hosting C2 abuse + Tetrade framework signature cited in essentially all subsequent fileless malware + LOLBin abuse + Latin American banking trojan industry analyses through 2015-2026 period.